1) Confound 2) Contradict 3) Disprove 4) French word used in English 5) Negate 6) Overwhelm by argument 7) Prove to be false 8) Prove wrong 9) To bring to naught 10) To disprove or refute 11) To show to be false or wrong Found on https://www.crosswordclues.com/clue/confute
Con·fute transitive verb [ imperfect & past participle Confuted ; present participle & verbal noun Confuting .] [ Latin confutare to chek (a boiling liquid), to repress, confute; con- + a root seen in futis a water ... Found on http://www.encyclo.co.uk/webster/C/135
to prove to be false, invalid, or defective; disprove: to confute an argument. · to prove (a person) to be wrong by argument or proof: to confute one's opponent. · to bring to naught; confound. Found on https://www.infoplease.com/dictionary/confute