untrue 18 synonyms and 8 antonyms for untrue, ranked by how commonly they're used. Adjective — Not true; false. Synonyms for untrue counterfactual erroneous fallacious false fictitious inaccurate invented incorrect made up nonfactual nontrue nontruthful pseudo- spurious untruthful unveracious unveridical wrong Antonyms for untrue accurate correct factual right truthful true veracious veridical ← Back to the full definition of untrue
