The vertical distance above a reference point, typically sea level. Often used interchangeably with elevation but technically refers to height in the atmosphere.

A persistent body of dense ice that moves under its own weight, carving valleys and shaping mountain landscapes over millennia.

A large tower or block of glacial ice found on steep glaciers, formed where crevasses intersect. Seracs can collapse without warning.

An accumulation of rocks, sediment, and debris deposited by a glacier. Terminal, lateral, and medial moraines indicate past and present glacial activity.

The gradual physiological adaptation to decreased oxygen at higher altitudes, typically following a "climb high, sleep low" pattern.

A staging area at the foot of a mountain from which climbing expeditions are launched, stocked with supplies and used for acclimatization.

Altitudes above approximately 8,000 meters where oxygen is insufficient to sustain human life for extended periods, causing progressive deterioration.

Any of the 14 mountains on Earth with summits above 8,000 meters, all located in the Himalayas and Karakoram ranges.