1382, "to cut with a stroke of a blade or whip," perhaps from M.Fr. esclachier "to break," variant of esclater "to break, splinter" (see slat). In ref. to prices, it is attested from 1906. The noun meaning "a cutting stroke with a weapon" is recorded from 1576; sense of "slit in a garment" is from 1615; that of "open tract in a forest" is first attested 1825, Amer.Eng. As a punctuation mark in writing or printing, it is recorded from 1961. Slash-and-burn method of clearing forest for cultivation is from 1919.
c.1300, "a skirmish, fight," bikern, probably from M.Du. bicken "to slash, stab, attack," + -er, M.E. frequentative suffix. Meaning "quarrel" is from early 14c.
1540s, from M.E. garce (early 13c.), from O.N.Fr. garser "to scarify, cut, slash," apparently from V.L. *charassare, from Gk. kharassein "engrave." Loss of -r- is characteristic (see bass, bust, etc.). Slang use for "vulva" dates to mid-1700s.
1547, alteration of racen "pull or knock down" (a building or town), from earlier rasen (14c.) "to scratch, slash, scrape, erase," from O.Fr. raser "to scrape, shave," from M.L. rasare, frequentative of L. radere (pp. rasus) "to scrape, shave," perhaps from PIE *razd- (cf. L. rastrum "rake"), possible extended form of PIE base *red- "to scrape, scratch, gnaw" (see rodent).