concierge (n.)

1640s, from French concierge "caretaker, doorkeeper of a hotel, apartment house, prison, etc., porter" (12c.), of uncertain origin. Perhaps from Vulgar Latin *conservius, from Latin conservus "fellow slave," from assimilated form of com "with, together" (see con-) + servius "slave" (see serve (v.)). In France, formerly the title of a high royal official. Related: Conciergerie (c. 1600).