early 15c., "to prolong, extend," from Old French proroger, proroguer (14c.), from Latin prorogare, literally "to ask publicly," from pro "before" (see pro-) + rogare "to ask, inquire, question; ask a favor," also "to propose (a law, a candidate);" see rogation. Perhaps the original sense in Latin was "to ask for public assent to extending someone's term in office." Legislative meaning "discontinue temporarily" is attested from mid-15c. Related: Prorogation.
