late 14c., "act or fact of obeying," from Old French obeissance "obedience, service, feudal duty" (13c.), from obeissant, present participle of obeir "obey," from Latin oboedire (see obey). Sense in English altered late 14c. to "bending or prostration of the body as a gesture of submission or respect" by confusion with abaisance. Related: Obeisant.
