ETYM Pref. in- not + contestable: cf. French incontestable.
1. Incapable of being contested or disputed; SYN. incontestible.
2. Not open to question; obviously true; SYN. indisputable, undisputable.
That cannot be refuted; unanswerable; indisputable; unbreakable.
ETYM Latin irrefutabilis: cf. French irréfutable. Related to Refute.
Incapable of being refuted or disproved; indisputable.
In an irrefutable manner, incontrovertibly, indisputably