crevasse

Short definition from Wiktionary

Noun

1. 1
   A crack or fissure in a glacier or snowfield; a chasm.
2. 2
   A breach in a canal or river bank.
3. 3
   Any cleft or fissure.
4. 4
   A discontinuity or “gap” between the accounted variables and an observed outcome.

Verb

1. 1
   To form crevasses.
2. 2
   To fissure with crevasses.