simple past tense and past participle of doubt

Subject to, or causing doubt. / Experiencing or showing doubt, sceptical. / Undecided or of uncertain outcome. / (obsolete) Fearsome, dreadful. / Improbable or unlikely.

plural of doubt

Third-person singular simple present indicative form of doubt

A doubtful person or thing.

(uncountable, countable) Disbelief or uncertainty (about something); (countable) a particular instance of such disbelief or uncertainty. / (countable, obsolete or India) A point of uncertainty; a query.

(transitive, intransitive) To be undecided about; to lack confidence in; to disbelieve, to question. / (transitive, archaic) To harbour suspicion about; suspect.

A condition of doubt.

present participle of doubt

without a doubt; surely.