incontrovertibly UK /ɪnˌkɒn.tɹəˈvɜː(ɹ).tɪ.bli/US /ˌɪnˌkɑn.tɹəˈvɝ.tə.bli/ adverb1 •In an incontrovertible manner; in a manner not capable of being denied, challenged, or disputed.In such a case and under such proof the intent to kill and the deliberate and premeditated malice are incontrovertibly implied. — 1917 formsmore incontrovertibly · most incontrovertibly