undebatably

un·de·bat·a·ble

U0045900 (ŭn′dĭ-bā′tə-bəl)adj. Closed to debate or further discussion: undebatable facts.
un′de·bat′a·bly adv.

undebatably

(ˌʌndɪˈbeɪtəblɪ) advin an undebatable manner