punctuation symbol introduced for computer purposes, by 1977, from back (adj.) + slash (n.).
Entries linking to backslash
back adj.
"being behind, away from the front, in a backward direction," Middle English, from back (n.) and back (adv.); it is often difficult to distinguish from these when the word is used in combinations. Formerly with comparative backer (c. 1400), also backermore. To be on the back burner in the figurative sense of "postponed" is by 1960, from the image of a cook keeping a pot there to simmer while at work on another concoction at the front of the stove.
slash n.
"a sweeping or cutting stroke with an edged weapon," 1570s, from slash (v.). The sense of "slit cut into the stuff of a garment," to show a different material beneath, is from 1610s. As a punctuation mark in writing or printing, it is recorded from 1961.
The meaning "open tract in a forest" is attested by 1825, American English, from being cut clear of trees. The slash that means "swampy ground, wet bottom land" (1650s) is said to be a different word, of obscure origin.