early 15c., "conjuring tricks, sleight of hand," from Old French léger de main "quick of hand," literally "light of hand." Léger "light" in weight (Old French legier, 12c.) is from Latin levis "light" (from PIE root *legwh- "not heavy, having little weight"). It is cognate with Spanish ligero, Italian leggiero "light, nimble" (hence also leger line or ledger line in music). Main "hand" is from Latin manus (from PIE root *man- (2) "hand").
late 14c., "one skilled in magic or sorcery," from Old French magiciien "magician, sorcerer," from magique (see magic (n.)). As "practitioner of legerdemain," by 1590s.
From c. 1400 as "deceive, put (someone) under a spell." Especially of tricks of manual dexterity and legerdemain from mid-15c. Figurative use, of careers, husbands, etc., is by 1940. Related: Juggled; juggling.
late 14c., magike, "art of influencing or predicting events and producing marvels using hidden natural forces," also "supernatural art," especially the art of controlling the actions of spiritual or superhuman beings; from Old French magique "magic; magical," from Late Latin magice "sorcery, magic," from Greek magike (presumably with tekhnē "art"), fem. of magikos "magical," from magos "one of the members of the learned and priestly class," from Old Persian magush, which is possibly from PIE root *magh- "to be able, have power."
The transferred sense of "legerdemain, optical illusion, etc." is from 1811. It displaced Old English wiccecræft (see witch); also drycræft, from dry "magician," from Irish drui "priest, magician" (see Druid). Natural magic in the Middle Ages was that which did not involve the agency of personal spirits; it was considered more or less legitimate, not sinful, and involved much that would be explained scientifically as the manipulation of natural forces.