cleft
n.n. a split or a gap in something, like a rock or a piece of wood. In language, it describes a sound or word that was originally one sound but has split into two.
n. a split or fissure in a solid mass; in linguistics, a phonological process where a single sound splits into two distinct sounds over time.
The deep cleft in the rock was formed by years of erosion.
Linguists study how a cleft in the vowel sound eventually led to the creation of two distinct phonemes in the modern language.
The geological survey revealed a narrow cleft in the limestone bedrock that had remained hidden beneath layers of sediment for millions of years.
From Middle English clift, from Old English ġeclyft, from Proto-West Germanic klufti, from Proto-Germanic kluftiz, equivalent to cleave + -t (“-th”). Compare Dutch klucht (“coarse comedy”), Swedish klyft (“cave, den”), German Kluft. See cleave.