Old English dust, from Proto-Germanic *dunstaz (cf. Old High German tunst "storm, breath," German Dunst "mist, vapor," Danish dyst "milldust," Dutch duist), from PIE *dheu- (1) "dust, smoke, vapor" (cf. Sanskrit dhu- "shake," Latin fumus "smoke"). Meaning "that to which living matter decays" was in Old English, hence, figuratively, "mortal life."
Literally, to fall face down in the dirt; to suffer a defeat: “Once again, the champion wins, and another contender bites the dust.”
Narcotics in powder form (1960s+ Narcotics)