gash / gash/ • n. 1. a long deep slash, cut, or wound: a bad gash in one leg became infected. ∎ a cleft made as if by a slashing cut: the blast ripped a 25-foot gash in the hull.2. vulgar slang the vulva. ∎ offens. women collectively regarded in sexual terms.• v. [tr.] make a gash in; cut deeply: the jagged edges gashed their fingers.