Synonyms and related words :
acknowledge, affirm, allege, and candle, announce, approve, argue, assert, assert under oath, asseverate, assure, authenticate, aver, avouch, avow, back, back up, be sponsor for, bear out, bear witness, bespeak, betoken, bolster, bond, book, breathe, buttress, certify, circumstantiate, confirm, connote, corroborate, countersecure, declare, demonstrate, denote, depone, depose, disclose, display, document, endorse, ensure, evidence, evince, exhibit, express, fortify, furnish evidence, give evidence, give indication of, go to show, guarantee, guaranty, illustrate, imply, indicate, insure, involve, kiss the book, manifest, mark, point to, probate, prove, ratify, reinforce, secure, set forth, show, show signs of, sign, sign for, signalize, signify, speak for itself, speak volumes, sponsor, stand behind, stand up for, strengthen, subscribe to, substantiate, suggest, support, sustain, swear, swear by bell, swear the truth, swear to, swear to God, swear to goodness, symptomatize, tell, tend to show, testify, undergird, undersign, underwrite, uphold, validate, verify, vouch, vouch for, vouchsafe, vow, warrant, witness