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.
"thin flat piece of snow; a particle," early 14c., also flauke, flagge, which is of uncertain origin, possibly from Old English *flacca "flakes of snow," or from cognate Old Norse flak "flat piece," from Proto-Germanic *flakaz (source also of Middle Dutch vlac, Dutch vlak "flat, level," Middle High German vlach, German Flocke "flake"); from PIE root *plak- (1) "to be flat." From late 14c. as "a speck, a spot."