Word Origin & History
O.E. slidan "move smoothly, glide," from P.Gmc. *slidanan (cf. O.H.G. slito, Ger. Schlitten "sledge"), from PIE base *(s)lei- "slide" (cf. Lith. slystu "to glide, slide," O.C.S. sledu "track," Gk. olisthos "slipperiness," olisthanein "to slip," M.Ir. sloet "slide"). Phrase to let (something) slide is
recorded from c.1386. The noun is 1570, from the verb. Meaning "picture prepared for use with a projector" is attested from 1819 (in magic lantern shows). Slider as a type of baseball pitch is recorded from 1936. Slide-rule as a calculating tool is from 1838.