Bergschrund (Schrund): Crevasses that are formed on the upper portion of glacier from where the moving section of the glacier pulls away from the head wall are called Bergschrund.
Moat: A moat is a gap between the top edge of a glacier and the upper portions of the mountain face.
Cairn: A pile of rock, wood or both used to mark a route or route junction in the mountains or trekking region
Crevasses: A crack in a glacier surface is referred to as Crevasse. Crevasses vary in width and depth and are often concealed by surface snow and can be open or concealed. In the lower part of a glacier the crevasses are open. Above the snow-line they are frequently hidden by arched-over accumulations of winter snow. The detection of hidden crevasses requires care and experience. After a fresh fall of snow they can only be detected by sounding with the pole of the ice axe, or by looking to right and left where the open extension of a partially hidden crevasse may be obvious. The safeguard against accident is the rope, and no one should ever cross a snow-covered glacier unless roped to one, or even better to two companions. Anyone venturing onto crevasses should be trained in crevasse rescue. Concealed crevasses are a hazard for climbers on glaciers.
Cornice: Wind-sculpted snow overhanging a ridge; a hazard to avoid by not walking on or in the fall line below it.
Chimney: A rock route large enough for the climber to fit inside.
Glaciers: When traveling over glaciers, crevasses pose a grave danger. These giant cracks in the ice are not always visible as snow can be blown and freeze over the top to make a snow bridge. At times snow bridges can be as thin as a few inches. Climbers use a system of ropes to protect themselves from such hazards. Basic gear for glacier travel includes crampons and ice axes. Teams of two to five climbers tie into a rope equally spaced. If a climber begins to fall the other members of the team perform a self-arrest to stop the fall. The other members of the team enact a crevasse rescue to pull the fallen climber from the crevasse.
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 slow going and is only done when alternative routes would take even more time.
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.
Spur: A rock or snow rib on a mountain; a lateral ridge.
Ice Slopes: Mountaineers descending mixed rock, snow and ice slope in winter High Tatras. For travel on slopes consisting of ice or hard snow, crampons are a standard part of a mountaineer's equipment. While step-cutting can sometimes be used on snow slopes of moderate angle, this can be a slow and tiring process, which does not provide the higher security of crampons. However, in soft snow or powder, crampons are easily hampered by balling of snow, which reduces their effectiveness. In either case, an ice axe not only assists with balance but provides the climber with the possibility of self-arrest in case of a slip or fall. On a true ice slope however, an ice axe is rarely able to effect a self-arrest. As an additional safety precaution on steep ice slopes, the climbing rope is attached to ice screws buried into the ice.
True ice slopes are rare in Europe, though common in mountains in the tropics, where newly-fallen snow quickly thaws on the surface and becomes sodden below, so that the next night's frost turns the whole mass into a sheet of semi-solid ice.
Snow Slopes: Snow slopes are very common, and usually easy to ascend. At the foot of a snow or ice slope is generally a big crevasse, called a bergschrund, where the final slope of the mountain rises from a snow-field or glacier. Such bergschrunds are generally too wide to be stepped across, and must be crossed by a snow bridge, which needs careful testing and a painstaking use of the rope. A steep snow slope in bad condition may be dangerous, as the whole body of snow may start as an avalanche. Such slopes are less dangerous if ascended directly, rather than obliquely, for an oblique or horizontal track cuts them across and facilitates movement of the mass. New snow lying on ice is especially dangerous. Experience is needed for deciding on the advisability of advancing over snow in doubtful condition. Snow on rocks is usually rotten unless it is thick; snow on snow is likely to be sound. A day or two of fine weather will usually bring new snow into sound condition. Snow cannot lie at a very steep angle, though it often deceives the eye as to its slope. Snow slopes seldom exceed 40°. Ice slopes may be much steeper. Snow slopes in early morning are usually hard and safe, but the same in the afternoon are quite soft and possibly dangerous; hence the advantages of an early start.
Saddle (Col, Low Point): The lowest point of elevation between two peaks. A col more often refers to a low point between two lesser points, for example, a low point in a ridge. Saddles and cols are common waypoints in routes because routes often follow the low ground.
Traverse: Moving laterally across terrain instead of ascending or descending.
Glissading: This method of descending can be pure joy, dropping a thousand feet of elevation in minutes, under control. Don’t glissade a slope you have not climbed up except for short easy stretches that you can fully observe.
Base Camp: The 'Base Camp' of a mountain is an area used for staging an attempt at the summit. Base camps are positioned to be safe from the harsher conditions above. There are base camps on many popular or dangerous mountains. Where the summit cannot be reached from base camp in a single day, a mountain will have additional camps above base camp. For example, the southeast ridge route on Mount Everest has Base Camp plus (normally) camps I through IV.
Bivouac (Bivy, Bivi): A high camp, not always a planned overnight stop.
Shelter: Climbers use a few different forms of shelter depending on the situation and conditions. Shelter is a very important aspect of safety for the climber as the weather in the mountains may be very unpredictable. Tall mountains may require many days of camping on the mountain.
Snow Cave: Where conditions permit snow caves are another way to shelter high on the mountain. Some climbers do not use tents at high altitudes unless the snow conditions do not allow for snow caving, since snow caves are silent and much warmer than tents. They can be built relatively easily, given sufficient time, using a snow shovel. A correctly made snow cave will hover around freezing, which relative to outside temperatures can be very warm. They can be dug anywhere where there is at least four feet of snow. Another shelter that works well is a quinzee, which is excavated from a pile of snow that has been work hardened or sintered (typically by stomping). Igloos are used by some climbers, but are deceptively difficult to build and require specific snow conditions.
Tent: Tents are the most common form of shelter used on the mountain. These may vary from simple tarps to much heavier designs intended to withstand harsh mountain conditions. In exposed positions, windbreaks of snow or rock may be required to shelter the tent. One of the downsides to tenting is that high winds and snow loads can be dangerous and may ultimately lead to the tent's failure and collapse. In addition, the constant flapping of the tent fabric can hinder sleep and raise doubts about the security of the shelter. When choosing a tent, alpinists tend to rely on specialized mountaineering tents that are specifically designed for high winds and moderate to heavy snow loads.
Fixed Rope: 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 for extra climbing assistance and protection.
Rappelling (Rap, Abseil): To descend a fixed rope, usually by means of a braking device. Statistically the most dangerous climbing activity probably because too many 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 alternative for the last person is to down climb the pitch while being top roped.
Top Rope: A climbing rope anchored above both the climber and the belayer; to belay someone from below using a rope that loops up through a high anchor and then back down to the climber.