fill in

1 to give information to my friend quickly filled me in on the portion of the movie that I had missed Synonyms acquaint, advise, apprise, brief, catch up, clear, clue (in), familiarize, enlighten, hip, inform, instruct, tell, verse, wise (up)Related Words advertise, alert, notify; announce (to), disclose (to); assure, certify, convince, reassure, warrant; educate, lecture, school, teach, tutor; disabuse, disenchant, disillusion, undeceiveNear Antonyms misinform, mislead

2 to serve as a replacement usually for a time only she's only filling in while the regular secretary is on vacation Synonyms cover, pinch-hit, stand in, step in, sub, substitute, take overRelated Words understudy; relieve, spell; double (as)