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Glossary of rock, ice and mountain climbing terms

Plan BAlpine: Concerning high mountains, originally, concerning the Alps.

Alpine start: An early morning start to ascend before the sun softens the snow or to return before nightfall.

Alpine style: Lightweight, fast climbing that emphasizes the role of speed in safety, to climb and return quickly during a window of good weather.

AMS (acute mountain sickness, hypoxemia, hypoxia): Symptoms of low blood oxygen due to high altitude: headache, loss of appetite, nausea, vomiting, malaise and disturbed sleep. Also see HADE below.

Anchor: A point where the rope is secured to the snow, ice or rock to provide protection against a fall. An equalized anchor system places equal weight on multiple devices to reduce the chance of failure. Any individual anchor point, whether one piece of protection or an anchor system, must be able to hold a fall. The condition of the rock, snow or ice determines whether an individual anchor device or an anchor system is required to provide adequate security.

Approach: The nontechnical section of the climb that leads to the technical part of the climb.

Ascender (Jumar, Clog): A mechanical braking device used for belaying oneself from a vertical fixed rope. By contrast, for a traverse protected by horizontal fixed line, carabiners on slings are often used to connect the climber to the main rope. As carabiners have no braking capability, a climber will fall to the lower anchor or to the lowest point between two anchors. Self-belay from prusik or bachmann knot is a known unsafe technique. Unlike a carabiner, prusik cord burns through quickly once it begins sliding on the main line.

Avalanche: Movement down the mountain of previously stationary snow, rock, or both. Snow avalanche conditions for open slopes can often be predicted by monitoring the weather. As days of high avalanche danger and known avalanche areas are generally avoided, more climbers are injured by a single falling rock or piece of ice.

Bachmann (bachman) knot: A friction knot similar in design and purpose to a prusik knot with the difference that the Bachmann can be set up in a self-regulating configuration. When used in a z-pulley, when tension is released the Bachmann slides along the main rope. When tension pulls the knot tight, the knot prevents downward motion of the pulley. Although similar in purpose to an ascender, a Bachmann knot will burn quickly through the prusik cord should it begin to slip.

Base weight: The weight of a pack before food, fuel and water. Some thru-hikers flirt with hypothermia by skimping on two warm and dry items to reach a base weight below 10 pounds, 4.5 kilograms, by omitting a stove and carrying a single-wall shelter instead of a double-wall tent. Together, these safety upgrades can sum to as little as 2 additional pounds, 1 kilogram. Dry hiking reduces weight by carrying only enough water to reach the next known water source, another way to leave oneself unprepared for an emergency. A mountaineer's pack loaded with safety gear — a helmet, a harness, a rope plus the appropriate protection for the route — is often not weighed. What is, is. "That is the question: Whether 'tis nobler in the mind to" remain indifferent about "what the meaning of the word 'is' is," and about whom is boasting of a light pack as they toss their sleeping bag into another's tent. "Or to take arms against a sea of troubles." Either way, base weight is likely to be about the same.

Belay: A safety technique where a stationary climber provides protection by means of ropes, anchors and braking devices or techniques, to an ascending or descending partner. A static belay is when a fall is held fast. A dynamic belay is when a fall is brought to a gradual stop by allowing the rope to slide somewhat to not overload the anchor with the force of the fall. Static belay is often used on ice and rock where the anchors are bombproof and the pitch is near vertical. Dynamic belay is often used on snow where the anchors are questionable and the slope is angled enough the climber can slide a small distance without injury.

Belay device (ATC, figure eight): A metal device through which a climbing rope is threaded to create friction to brake a fall. Many belay devices can double as a rappel device. An ATC makes a fine belay device but the wire can be pulled into the device when using it as a rappel device. A figure eight is difficult to work as a belay device but is a reliable rappel device.

Belay station: An anchored position from where a climber provides roped protection for a partner climbing.

Bergschrund (schrund): A gap or crevasse that appears near the head of a glacier where the neve field portion of the glacier joins the valley portion of the glacier. A moat is a gap between the top edge of a glacier and the upper portions of the mountain face. Schrunds and moats can create obstacles.

Bivouac (bivy, bivi): A high camp, not always a planned overnight stop.

Bollard: An anchor in snow or ice created by cutting or shaping the surface so a rope or sling can encircle the feature.

Bolt: A substantial metal pin drilled in the rock to provide permanent protection, a type of anchor rejected by Trads.

Boot-ax belay: A belay technique used on snow where the climbing rope is wound around both a firmly planted ice ax shaft and the belayer's boot. Boot-ax belay usually requires an anchor in addition to the ax. As with belay from many types of snow anchors, a dynamic belay (see the video linked above) will reduce the odds of anchor failure.

Boulder: To climb a difficult, but short, rock pitch where a potential fall will be of minimal consequence.

Cairn: A pile of rock, wood or both used to mark a route or route junction.

Cam: A mechanical spring-loaded device that can be inserted in rock cracks through which a climbing rope can be threaded for protection.

Carabiner (biner): Forged aluminum devices of various shapes (oval, D, etc.) with a spring-loaded gate through which a climbing rope can be threaded, used to connect to protection or to provide connections in an anchor. The gate of a locking carabiner can be locked closed for increased security. Two regular carabiners with opposed gates can replace safely one locking carabiner.

Chimney: A rock route large enough for the climber to fit inside and use the relative wealth of holds from both sides of the chimney.

Clean: To remove protection (cams, pickets, etc.), usually the responsibility of the last climber in a rope team.

Clipping in: Using a carabiner to connect to belays and anchors or to connect ropes to protection.

Cornice: Wind-sculpted snow overhanging a ridge, a hazard avoided by not walking on the cornice or in the fall line below it.

Couloir: A gully, sometimes a potential route. A chute or bowling alley is steep enough for rock or ice fall to be a concern.

Crampons: Spiked metal devices that attach firmly to climbing boots to provide reliable footing on ice and firm snow slopes.

Crevasse: A crack in a glacier surface. Crevasses vary in width and depth and are often concealed by surface snow that forms a snow bridge. Concealed crevasses are one hazard on glaciers. The other is falling rock.

Deadman: Any device (picket, shovel, bag of snow) buried in snow to serve as an anchor.

Dial in (dialed, wired): Knowing a route well from having climbed the same pitch or mountain repeatedly. A similar concept is hanging on a rope in the same place to practice moves repeatedly, a practice known as hangdog or dog. A legitimate question to ask a climb organizer is, "Do you have the route dialed in?" Experienced climbers often go exploring together. New climbers should consider limiting themselves to climbs dialed in by one or more climb participants. Snow routes change frequently enough to evade getting dialed in.

Double-wall tent: A tent that, even within tight confines, protects sleeping bags from condensation — and occupants from hypothermia — by adding an interior wall between the rain fly and the sleeping bag. In reliably-warm conditions, 3-season tents are preferred as they offer the best ventilation and the least weight. In conditions that might be hot or cold, 3 to 4-season tents convert as appropriate by multiple doors and vents that can be left opened or closed. A 3 to 4-season tent secured in 4-season mode is wonderfully warm and dry almost no matter what is happening outside. Only in reliably-wintry conditions are exclusively 4-season tents appropriate.

Down climb: Descending a pitch often requires more skill than climbing up and therefore provides good practice for the climber and, sometimes, the belayer. Because down climbing is statistically safer than rappelling, down climbing is preferred to rappelling when time allows.

Dry-tool: To ascend a section of rock using ice tools, a technique used for short sections of rock between sections of snow or ice on alpine climbs.

Edging: A rock climbing technique where the edges of the climbing shoes are used to stand on small footholds. By contrast, smearing applies as much of the sole of the climbing shoe as possible to a rock slab to achieve maximum friction.

Exposure: The distance from the climber to where the climber would likely stop in the event of an unprotected fall.

Fall: To lose involuntarily one's position. Short falls onto protected rope tend to be silent since there is insufficient time to make a sound. Often the belayer has no information except the rope going tight. A screamer is long enough to provide the luxury of vocal panic. A whipper is similar to a screamer but the vocal routine returns to normal when the rope catches the fall. A crater ends when the climber hits the ground.

Fall! (falling!): What climbers in the vicinity yell to protect their team and others when someone is in a fall.

Fall line: The direction a fall will take. The belay position and belay anchors must be in line with the fall line to prevent a pendulum effect. Avoid climbing in the fall line of another climber higher on the pitch, of a cornice or anything else that might come down the mountain. When traversing a glacier, stay lower on the glacier than the collection of rocks that have fallen onto the glacier.

Figure-eight knot: The basic climber's knot, when retraced, used to attach a climber's harness to the rope and for many other purposes. Not to be confused with a figure-eight belay and rappel device.

Fisherman's knot (double fisherman's knot): A knot used to make small-diameter rope, like prusik, into slings. For large-diameter ropes, use a figure-eight knot to connect them as a figure-eight knot will better slide over obstacles without becoming caught.

Fixed rope / fixed line traverse: A rope anchored to a route by the lead climber and left in place for others who follow, a mechanical ascender or, on a traverse, clipped-in carabiners sliding along the rope can be used both for climbing assistance and for protection.

Flat footing (French technique): Keeping all crampon points in the ice by walking backwards or sideways.

Fluke: A dynamic snow anchor that dives deeper as it moves. For use in soft snow where pickets will pull out. Because a fluke slows a fall rather than stops a fall, flukes should only be used on pitches where slowing a fall provides adequate protection.

Free climb: To climb using only one's hands and feet without artificial aids. A belay rope may be employed. As opposed to aid climb.

Free solo: To free climb without a belay rope and to accept a crater as the potential consequence of a long fall.

Front pointing: A technique for ascending steep or overhanging ice where the extended front points of the crampons provide grip by biting into the ice.

Gendarme: A mass of rock protruding from a ridge that forces the route from the top of the ridge to its side. From the French word for constable or police.

Girth hitch: A knot made by looping the end of a sling over itself, often used to attach to anchors, to connect multiple slings for a longer sling, and to connect one's ice ax to the harness.

Glissade: Descending moderate snow slopes under control by sliding on one's feet or rump. Glissading steep or icy slopes is the cause of many of mountaineering accidents. Glissading only works in snow. Glissading does not work on ice and on hard crust where self-arrest cannot slow and stop a fall.

Gym rat: One of many often colorful terms for persons who, with swagger, assert they know climbing because they climb in rock gyms. When rock and mountain climbing, they often become frightened because they are nubs (aspiring newbies) regarding anchors and protection.

HACE (high altitude cerebral edema): Swelling of the brain due to cell death and fluid increase, the most serious form of altitude sickness.

HADE (high altitude dumb): Temporary intelligence loss due to reduced oxygen in the blood supplying the brain. Unlike HACE and HAPE, HADE often occurs at modest altitudes and can be artificially induced at sea level by drinking excessive bourbon, etc.

HAPE (high altitude pulmonary edema): Fluid buildup in the lungs. Can lead to HACE if descent is not immediate.

Harness: A strong belt with leg loops made of nylon webbing used to secure the climber to the rope, often with loops to hold climbing hardware. A chest harness is sometimes worn in addition to a waist harness to prevent an inverted fall, for example, when crossing a glacier with a heavy pack.

Headwall: The upper section of a mountain where the terrain is set off from the terrain below by being more steep.

Hexcentric (hex): A hexagon-shaped nut attached to a flexible looped wire for insertion into a rock crack for protection.

Hiker hunger: The need to consume more than the usual amount of food after as little as one day on the trail, the reason planned food allowances often fall short. A cold ambient temperature adds to the effect. Becoming cold, as evidenced by shivering, further adds to the effect.

Hypothermia: Low body temperature caused by cold ambient temperature, more likely when having become wet and when not carrying a heat source, perhaps only for unanticipated circumstances. Although easy to prevent, hypothermia is the most common cause of death in the wilderness.

Ice ax (axe): A mountaineering tool for snow and ice climbing, pointed at the base of the shaft and with a head consisting of a pick and an adze. A standard ax shaft may be 60 to 75 cm in length while technical axes are typically 50 cm long. Second or third tools may be shorter yet, 38-45 cm.

Ice hammer: A variant of the ice ax where the head consists of a pick and a hammer, usually used in combination with an ice ax. The hammer is used to pound in protection like flukes and pickets.

Ice screw: A threaded piton designed to bore into ice securely enough to serve as an anchor.

Jam: To wedge or jam body parts — fingers, a hand, a foot, etc. — into cracks and apply torque to adhere to the rock. Both strenuous and remote from ordinary experience, jamming is difficult to learn and requires real rock to do so as gyms do not replicate cracks well. Once mastered, jamming often becomes the hold of choice by crackmasters.

Lead (sharp end of the rope, on point): To be the first climber up a pitch and to place protection along the way while being belayed by a partner from below.

Lieback (layback): A technique where the climber's hands pull one way and the feet push the opposite way.

Mixed climbing: Ascending a route involving a combination of snow, rock or ice.

Moraine: A random accumulation of boulders, rocks, scree and sand carried down the mountain and deposited by a glacier. Crossing a moraine is not especially dangerous but is slow going and is only chosen when alternative routes would take even more time.

Multi-pitch climb: A technical climb that is longer than a single rope length, thus requiring multiple anchors and belay stations.

Nut (stopper): A metal wedge with a wire loop for insertion into cracks in rock for protection.

Picket: A "T" shaped length of aluminum 2' to 3' long pounded or buried in the snow for protection.

Pitch: A section of climbing between two belay points, no longer than the length of a climbing rope.

Piton: A metal spike that can be hammered into rock cracks for protection, a type of anchor rejected by Trads as climbers leave pitons in the rock.

Plan B: The consequences of a fall. A good Plan B generally involves being caught by a protected rope. A bad Plan B involves probable injury. When conditions do not allow for any good Plan B, for example, snow too soft to hold protection, the appropriate course is to turn around. Loop routes are inherently more hazardous than ascending and descending the same route because climbers forfeit the opportunity to assess a Plan B for the descent route. For example, ascending by a route that can only hold protection before the sun warms it, then descending by another route does not allow the climbers to observe the condition of the descent route before having no choice but to take the route.

Protection (pro, fixation device): Any anchor — a nut, camming device, ice screw, fluke or picket — used during a climb to minimize the consequences of a fall. Intermediate protection is the pro used between two belay points. To maintain adequate speed, anchor systems are generally not used in intermediate protection.

Prusik (prussik, prussick, prussic): A sliding friction knot used to anchor a small diameter rope to a large diameter rope, also, to ascend a rope with prusik slings. The knot bears the last name of the Austrian climber who devised it.

PUDs (pointless ups and downs): A feature of poor trails and routes, sometimes an indication the person tasked with route finding should be replaced. Other features might include unsafe stream crossings, brush and downed trees obscuring and blocking the trail.

Rack: The collection of pro carried by a climber on waist harness loops and shoulder slings. A climber wearing a colorful rack bears a striking resemblance to a fanned peacock. It's difficult to stay in fashion because year to year, pastel, dark and neon colors go in and out of style. Black with white accents is always in good taste.

Rappel (rap, abseil): To descend a fixed rope, usually by means of a braking device, statistically the most dangerous climbing technique still in common use probably because some climbers rappel without a good Plan B, that is, without a belay. For the last person down a pitch there is no way to belay a rappel. For that reason the last person often rappels without a belay. An safer alternative, when possible, is for the last person to down climb the pitch while using the rope set up as a top-rope belay.

Required turn-around time: The time of day at which climbers must turn back in order to descend safely. Unanticipated slow going can cause climbers to reach the required turn-around time before reaching the summit. Climbers may also set a turn-around time in order to return the trailhead before dark, not necessarily for safety reasons.

Ridge walk: A trail above timberline and the immediate terrain often celebrated for the view, as close as backpackers get to the alpine vistas enjoyed by mountaineers.

Rime: A thin layer of ice and hard snow over rock. Verglas is a thin layer of ice over rock. Both are hazardous conditions that might end an ascent.

Rock!: What climbers in the vicinity yell to protect their team and others when nature or a climber sends a rock down the mountain. Often used to alert climbers of any falling object, ice, water bottles, etc.

Runnel: In common usage a rivulet or brook, in mountaineering, a groove in snow created by a falling cornice. Because crossing runnels is slow going, the prospect of crossing a series of runnels often ends an ascent.

Running belay: A similar technique to a fixed-line traverse except the rope moves with the climbers.

Runout: The distance between two points of protection, the distance between a lead climber and the last piece of protection, and the fall distance allowed by the distance from the last piece of protection.

Saddle (col): The lowest point of elevation between two peaks. A col more often refers to a low point between two lesser points, like a low point in a ridge. Saddles and cols are common waypoints in routes to eliminate unnecessary elevation gain and loss.

Scramble: Easy unprotected climbing.

Scree: Small loose rocks. Difficult to ascend, like climbing a slope of loose sand, scree slopes are often used for descents, a practice discouraged by Trads.

Second (follow): The climber who follows a lead up a pitch and belays from below while the lead advances, then ascends to the end of the pitch while often removing the intermediate protection.

Self-arrest: A technique that works in some snow conditions on moderate slopes to bring a fall to a stop. First, plant the ax pick to pivot the body below the ax on the slope. Then, while keeping the feet — more importantly, the crampons — off the surface, pull the ax handle under the chest to load weight onto the ax. When speed has slowed enough to lower the feet without causing a flip, then plant the feet firmly in the snow. Make a tripod of the feet and the ice ax. When a member of a fallen rope team, hold the position until determining the team will not begin sliding again if you release the anchor point. Self-arrest does not work in many conditions. Climbers must be aware of the general conditions where it will work, test specific conditions to see if it will work, then adjust the climb plan accordingly. Snow often softens during daylight hours and forms a hard ice crust at night. A slope that supports self-arrest in the morning often will not support self-arrest in the afternoon.

Self-belay: The essential technique for traveling on snow and ice. One or more ice axes are secured as anchors before the feet move. When both feet are in secure positions, then the ax or axes move to new positions. In this way secure, slow, progress is made. A solo climber will often use a wrist strap to the ax to avoid dropping the ax by accident. When traveling in a rope team, a sling connects the ax to the harness because holding a fallen rope team with only one's arm is untenable. The general rule is to stay in self-belay when another member of the rope team falls and resort to self-arrest only when falling yourself. As with self-arrest, self-belay does not work in many conditions. Climbing on snow requires ongoing tests of the snow conditions and assessment of the climb plan. Test to see if a planted ax handle or pick will hold a fall. Consider if softer snow later in the day will hold for the descent, or if hard crust late in the evening will allow planting an ax. Adjust the climb plan accordingly. Self-belay also refers to using an ascender or carabiners to attach oneself to a fixed line.

Sew up: To place protection close together along a route in excess compared to the common practice for the route. Sewing up good rock and hard snow routes adds to safety by reducing the potential fall distance and fall force reaching an anchor. In poor rock and soft snow, the safer technique is to use the same amount or more protection to create fewer anchor points, but to make each anchor point an anchor system.

Sling (runner): A length of nylon webbing or cord either sewn or tied into a loop used in conjunction with the rope and anchors to provide protection. A daisy chain is a sling sewn into loops so its length can be adjusted easily. A quickdraw is a sewn sling with a carabiner at each end.

Spindrift: Loose, powdery snow incapable of holding protection.

Sport climbing: Climbing a bolted rock route (sport route), a type of climbing with some of its own terminology. Pinkpoint and redpoint refer to the degree the route has been set up.

Spur: A rock or snow rib on a mountain, a lateral ridge.

Stem: To bridge the distance between two holds with one's feet, to push against adjacent or opposing walls with the feet as one might do in a chimney.

Talus: An accumulation of rock larger than scree that has fallen to its location. The presence and amount of talus should be considered when crossing a slope or climbing the pitch above it.

Thru-hiker: A hiker with a small backpack racing along long-distance trail end-to-end. The ideal for a thru-hiker is to maximize distance per day by minimizing gear and supplies, to walk barefoot, naked and, having adapted to life in the wild, to not to carry food or water, but to absorb nutrients from the aroma of flora while clacking along with trekking poles. Step off the trail to let thru-hikers by. They have a long way to go. To enjoy a few thru-hiking epics vicariously, read Carrot's blog at And now for something completely different, the ideal for a backpacker is a comfortable camp following a leisurely hike through one of the best places in the wild during ideal weather after the first freeze in the fall when the bugs are gone. A section hiker is not end-to-end hiking or end-to-ending, but is backpacking a portion of a long-distance trail, likely one of the better parts in a better season. For a day hiker, the ideal is the same as for a backpacker, but limited by the distance a day pack can support them, sufficient for many destinations. A slack-packer can be a day hiker, but is more generally someone not carrying complete overnight gear, but only enough to survive a night in an emergency, for example, a climber heading up from high camp with a lightweight summit pack. The ideal for a trail runner includes a trail in good enough condition they can steal glances away from where their feet will land to enjoy the wild.

Timberline: An elevation high enough trees no longer grow. The precise altitude varies by how sheltered an area is from inhospitable winter conditions. Not only trees, but what comes with a forest, insects are usually not found above timberline. While backpackers get bugged, ridge walkers and mountaineers at higher elevations hike and camp without bother. Mosquito alley is the section of trail between timberline and the trailhead, a distance mountaineers plan break locations around to hike through without a stop.

Top rope: A climbing rope anchored above both the climber and the belayer, to belay someone from below using a rope that loops up from the belayer through a high anchor and then back down to the climber.

Trad: A person who adheres to the principles of traditional climbing: to place and remove the protection used on a climb, to use no device or technique that will scar the rock or mountain.

Trail rhythm: A way of walking for increased speed on a good trail. The method begins with a slightly exaggerated, rhythmic forward and backward swinging of the arms. As a result, the posture becomes more erect, the stride becomes both longer and more steady. The left foot moves forward with the right arm, the right foot moves forward with the left arm. For impressive speed flailing, watch a thru-hiker add trekking poles to the technique. Minimizing stops improves overall speed. With some practice, the water bottles on a large backpack can be accessed without removing the pack. A small day-pack can be carried on one loose shoulder strap and pulled forward to access its contents in order to eat and drink while walking. When off trail, like on a typical summit route, horizontal progress is slow and difficult to predict. Instead of a horizontal measure of speed, mountaineers rely on a prior average vertical distance per hour to estimate their speed on the next mountain.

Traverse: Moving laterally across terrain instead of ascending or descending. Anchoring in with carabiners sliding along a fixed line is fine on a traverse. An ascender is required instead of carabiners when the fixed rope tilts more towards vertical.

Trekking Poles: Although ultramarathon runners will not bother with trekking poles even when thru-hiking, mere mortal thru-hikers and persons with knee problems are inclined to consider trekking poles the only essential piece of gear. Poles, which can be fashioned from downed tree branches, provide balance while crossing streams and other slippery, flat surfaces. The feet retain grip by supporting weight while delegating balance to the poles. Because backpacks have their own inertia, a hiker carrying an unusually heavy backpack can rely on poles for balance on any surface. On slight-uphill stretches of good trail, poles used correctly can increase one's speed. Other than for balance, poles require practice to be useful. Thru-hikers have more experience and find themselves on good trail more often than other hikers, so more often keep trekking poles in their hands even when only carrying them. Poles are a nuisance whenever the hands are wanted for something else, when eating and drinking, when preferring to keep your hands in your pockets, when wiping or blowing your nose, when scrambling and bouldering, when catching a fall, when off trail or on a poor trail where a pole can become stuck between rocks, and are a nuisance for the people behind you when on a dusty trail. Unless circumstances suggest trekking poles will be useful, they are often left at home or, just in case, carried on the pack.

Undercling: A hand hold on rock that depends on upward pressure on a downward hold.

Unzip (zipper fall, zip out): A fall where one piece of protection after another is pulled out by the force of the fall. Often refers to the failure of intermediate protection in rock climbing but is also a threat for fixed lines and for running belays in alpine climbing.

Water knot: A knot used to tie lengths of webbing together or into slings.

Webbing: Flat nylon tape or tubing used for slings and harnesses.

Yosemite/Tahquitz Decimal System: An evolving system to define route difficulty numerically with fine definitions within Class 5. The system bears the names of where it developed in the 1950s.

Z-pulley: A construction of climbing rope, carabiners and slings to leverage three to one the power of a few people so they can pull out a climber who collapsed a snow bridge and fell into a crevasse. A z-pulley plus a u-pulley (c-pulley) gives the rescuers twice the leverage of a z-pulley alone, six to one leverage, enough for one climber to haul out another.

Zero: From thru-hikers, to take a zero is to camp in the same place for a day and achieve no distance in order to rest, to acclimatize or to hang out in good company. A nero is a day where only a small distance is achieved.

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