1540s, from Middle English garce (early 13c.), from Old North French garser "to scarify, cut, slash" (Old French *garse), apparently from Vulgar Latin *charassare, from Greek kharassein "engrave," from PIE *gher- "to scrape, scratch" (cf. character). Loss of -r- is characteristic (see ass (n.2)). Slang use for "vulva" dates to mid-1700s.
1560s, alteration of garsen (late 14c.), from Old North French garser "to cut, slash" (see gash (n.)). Related: Gashed; gashing.
v. gashed, gash·ing, gash·es
To make a long, deep cut in; slash deeply. n.
A long, deep cut.
A deep flesh wound.
To do the sex act: We gashed (1980s+ Students)
Extra or unexpected portions, bits of luck, etc; dividends; bonuses
[WWII Army fr 1900s+ British Navy; origin unknown; perhaps fr French gache´, ''spoiled,'' since it occurs in gash bucket, ''garbage bin'']