mid-15c., "improper practice," from Old French abus (14c.), from Latin abusus "a using up" (see abuse (v.)). From 1570s as "violation, defilement" (surviving in self-abuse "masturbation," if at all). In reference to drugs by 1961. Modern use in reference to unwanted sexual activity is from late 20c. Earlier in Middle English was abusion "wicked act or practice, shameful thing, violation of decency" (early 14c.), "an insult" (mid-14c.), from Old French abusion, from Latin abusio.