indubitable \in-DOO-bi-tuh-buhl, -DYOO-\,
adjective:
that cannot be doubted; patently evident or certain; unquestionable.
And if there is an indubitable good within one's reach one stretches out one's hand.
-- Iris Murdoch, "The Nice and the Good," 1978
The change was indubitable. The difference between his present air and what it had been in the octagon room was strikingly great.
-- Jane Austen, "Persuasion," 1816
Indubitable is derived from the Latin word indubitābilis which had the same meaning.
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