Ascendeurs or Ascenders: a mechanical device used to ascend a fixed line. Will allow movement in one direction only, creating a handhold for the climber.
Avalanche: a release of ice or snow (either caused by humans or natural conditions) which sends the debris down the slope and can be extremely dangerous.
Barn door: an off balance move that causes a climber to pivot on two points of contact making it more difficult to cling to the rock
Belay: a method the climber uses to secure the rope to another person to catch a fall if that may occur
Beta: information about a route
Carabiner: a metal snap link through which climbing equipment (rope, protection) may be attached
Chalk: standard magnesium carbonate chalk to keep a climber's hands dry
Chimney: a parallel sided constriction wider than body width
Choss: loose, bad quality rock
Col: the lowest point on a ridgeline connecting two peaks
Couloir: a deep mountain gorge or gully
Crampons: steel frames with projecting spikes that are attached to the sole of the boots to prevent slipping on steep ice or snow.
Crevasses: Chris Warner uses the analogy of the glacier as a snickers bar. The glacier cracks in the same way a snickers bar would if you were to bend it. These cracks are the crevasses. As the glacier is forced to bend around/over obstacles crevasses are created.
Crux: the most crucial, difficult part of the climb
Dihedral: a flaring structure shaped much like an open book, often conducive to "stemming" techniques
Dry-tooling: the act of using your ice climbing tools to climb when there is no ice during an ice climb
Dyno: abbreviation for "dynamic movement", a move that requires momentum
Edge: a small horizontal hold; to stand on an edge with the corner of a shoe
Flag: to stretch out a leg in a way that improves balance
Free Climb: the use of only natural features of rock or artificial climbing holds to make upward progress on a route
Gaiters: Nylon material formed into a cuff that goes on over a mountaineers boot to prevent snow, ice or rocks from getting into the boot
Hand Jam: a climbing technique involving insertion of a hand into a constriction and expansion of the hand so that it will not pull out
Hoar frost: A particular kind of frost. Hoar frost forms when water vapor hits a freezing surface. It freezes immediately, leaving spikes called hoar frost. The temperature of the air is usually around freezing when there is hoar frost, but the ground must be a lot colder than freezing. The reason the air is warmer than the ground is because the air must be warm enough to carry water vapor.
Jug: a large, easy-to-hold feature
Jumar: a mechanical ascending device
Lay back: a move requiring pulling with arms to the side and pushing with the feet in the opposite direction
Lead: to climb starting with the rope on the ground clipping into protection points on the way up
Khumbu: the name of the major icefall which sits at the foot of Mt. Everest and also describes the general geographic region in which Mt. Everest lies
Lenticular: lens or ufo shaped clouds that form on top of or on the leeward side of mountains, often in wave patterns. they are indicative of very high winds and are usually seen on otherwise clear days.
Mantel: a climbing technique involving the transfer of upward force from a pulling action to a pushing action much like a child would climb the kitchen counter to reach the cabinets above
Moraine: a mass of rocks, gravel, sand, clay, etc. carried and deposited directly by a glacier, along its side (lateral moraine), at its lower end (terminal moraine), or beneath the ice (ground moraine)
Onsight: a clean ascent with no falls, first try with no prior knowledge of the route
Penitentes: these are ice formations that resemble small pyramids, created by the wind. These are often found in groups resembling a miniature forest.
Pinnacles: A spire of rock or ice
Pumped: referring to the state when the forearms are swollen and unresponsive
Rappel: the act of lowering oneself on a rope with a device to control the friction and speed of descent
Redpoint: a clean ascent with no falls, after initial attempt
Send: to complete a route successfully
Seracs: large towers/blocks of ice that are a part of a glacier system. Often unstable, these blocks are formed as the glacier drops over cliff bands. The glacier cracks and breaks off in these blocks
Slab: a ramp, any climb that is less than vertical
Smear: the act of placing a large surface area of shoe rubber on the wall to create maximum friction
Snow pickets: metal protection (2-3 feet long and formed in a T) used to secure the mountaineer on steep snow.
Stem: movement requiring opposing outward pressure much like a child climbing a door jam
Top rope: a climb that has the rope anchors preset at the top of the climb
Undercling: a hold that requires fingers to face upward rather than downward
Whipper: a big fall
Yosemite Decimal System: the most common system to rate route difficulty in the U.S.