Meaning

noun a wound made by cutting

noun a trench resembling a furrow that was made by erosion or excavation

noun a strong sweeping cut made with a sharp instrument

originFrom French gâcher (“to waste, to mess up”) or gâchis (“waste, a mess”), likely borrowed into English by ships' crews in the 19th century. Became increasingly vulgar by association with Etymology 1.

Etymology from Wiktionary, CC BY-SA 3.0