The Collaborative International Dictionary of English v.0.48:
convincing \convincing\ adj. causing one to believe the truth of something; having the power to influence or convince; cogent; -- of evidence or testimony; as, a convincing manner. Opposite of unconvincing. Note: [Narrower terms: disenchanting, disillusioning] [Also See: persuasive.] Syn: cogent, potent. [WordNet 1.5 +PJC]