Old English snaw "snow, that which falls as snow; a fall of snow; a snowstorm," from Proto-Germanic *snaiwaz (source also of Old Saxon and Old High German sneo, Old Frisian and Middle Low German sne, Middle Dutch snee, Dutch sneeuw, German Schnee, Old Norse snjor, Gothic snaiws "snow"), from PIE root *sniegwh- "snow; to snow" (source also of Greek nipha, Latin nix (genitive nivis), Old Irish snechta, Irish sneachd, Welsh nyf, Lithuanian sniegas, Old Prussian snaygis, Old Church Slavonic snegu, Russian snieg', Slovak sneh "snow"). The cognate in Sanskrit, snihyati, came to mean "he gets wet." As slang for "cocaine" it is attested from 1914.
early 14c., literally "a being driven" (at first of snow, rain, etc.); not recorded in Old English, it is either a suffixed form of drive (v.) (compare thrift/thrive) or borrowed from Old Norse drift "snow drift," or Middle Dutch drift "pasturage, drove, flock," both from Proto-Germanic *driftiz (source also of Danish and Swedish drift, German Trift), from PIE root *dhreibh- "to drive, push" (see drive (v.)).
"A being driven," hence "anything driven," especially a number of things or a heap of matter driven or moving together (mid-15c.). Figurative sense of "aim, intention, what one is getting at" (on the notion of "course, tendency") is from 1520s. Nautical sense of "deviation of a ship from its course in consequence of currents" is from 1670s. Meaning "controlled slide of a sports car" attested by 1955.