fess up

1 to accept the truth or existence of (something) usually reluctantly he fessed up to breaking the vase only after his guilt was obvious Synonyms acknowledge, agree, allow, concede, confess, admit (up), grant, own (up to)Related Words disburden, unburden, unload; affirm, avow, confirm, profess; accept, recognize, yield; announce, break, broadcast, communicate, declare, disclose, divulge, impart, proclaim, publish, reveal, spill, tell, unveil; betray, blab, expose, give away, inform, leak, rat, squeal, talk, tattle, tip (off), warn, wise (up); breathe, say, whisperNear Antonyms disallow, disavow, disclaim, disown; contradict, dispute, gainsay, negate, negative; rebut, refute, reject, repudiate; conceal, cover (up), hide, obscure, veil; kid (oneself)Antonyms deny

2 to make an acknowledgment of something unpleasant as true or valid he immediately fessed up once it was clear the cops had the goods on him Synonyms admit, cop (to) [slang], confess (up), own (up)Related Words blab, talk, tattle; babble, spillNear Antonyms clam up, hush, quiet (down), shut up