I. noun (plural yaks; also yak) Etymology: Tibetan (Lhasa dialect) yaʔ (spelled gyag Date: 1795 a large long-haired wild or domesticated ox ( Bos grunniens syn. B. mutus ) of Tibet and adjacent elevated parts of central Asia, see: yuk
III. intransitive verb also yack (yakked; also yacked; yakking; also yacking) Etymology: probably imitative Date: 1949 to talk persistently ; chatter ,
IV. noun also yack Date: 1950 persistent or voluble talk
