In a manner that leaves no possibility of doubt; undoubtedly.

clearly true; providing no possibility of doubt.

That which is indubitable.

plural of indubitable

The quality or state of being indubitable. / Something that cannot be doubted; a certainty.

(obsolete) To bring into doubt; to cause to be doubted.

Not questioned or doubtful; evident; certain.

The quality of being indubitable.

plural of indubitability

Third-person singular simple present indicative form of indubitate