Entry 2 senses · 2 variants Webster, 1913 confounding · IPA /kənfˈaʊndɪŋ/ adj. n. 01 adj. tending to contradict (a hypothesis). 1. tending to contradict (a hypothesis). Syn. contradictory. 02 n. a mistake that results from taking one thing to be another. 1. a mistake that results from taking one thing to be another. Syn. confusion, mix-up.