1) Be resistant to 2) Contradict 3) Debate 4) Deny 5) Discuss 6) Dispute 7) Oppose 8) Rebut 9) Refute 10) To argue about 11) To argue against Found on https://www.crosswordclues.com/clue/controvert
Con'tro·vert transitive verb [ imperfect & past participle Controverted ; present participle & verbal noun Controverting .] [ See Controversy .] To make matter of controversy; to dispute or oppose by reasoning; to contend against i... Found on http://www.encyclo.co.uk/webster/C/151