Word Origin & History
1529, "footman, running footman, valet," from M.Fr. laquais "foot soldier, footman, servant" (15c.), probably from O.Prov. lacai, from lecai "glutton, covetous," from lecar "to lick." Alternative etymology is via Fr. from Catalan alacay, from Arabic al-qadi "the judge." Yet another guess traces it through
Sp. lacayo, from It. lacchè, from Mod.Gk. oulakes, from Turk. ulak "runner, courier." This suits the original sense better, but OED says It. lacchè is from French. Sense of "servile follower" appeared 1588. As a political term of abuse it dates from 1939 in communist jargon.