- slide (v.)
- Old English slidan "move smoothly, glide," from Proto-Germanic *slidanan (cf. Old High German slito, German Schlitten "sledge"), from PIE root *(s)lei- "slide" (cf. Lithuanian slystu "to glide, slide," Old Church Slavonic sledu "track," Greek olisthos "slipperiness," olisthanein "to slip," Middle Irish sloet "slide"). Phrase to let (something) slide is recorded from late 14c. The noun is 1560s, 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.