Answer: A crack in the topmost section of a glacier.
Crevasse is a deep crack on the top most ice of a glacier. Crevasse forms where the ice is brittle. It is also known as glacial fracture. This results due to stress developed in the glacier ice. Crevasse usually form in the upper layer of the glacier where the ice is more brittle than deeper ice. Deeper ice does not break and fracture as the glacier moves.
