to be uncertain about (something); to be inclined to disbelieve (a statement, account, etc)
To doubt a proposition is to suspend judgment on it, to regard it as unsettled. René Descartes's ‘method of doubt’ required us to suspend judgment on anything that we can doubt: since fallible beliefs are untrustworthy, this is the only way to avoid error. Many recent thinkers urge that fallibility is no obstacle to our making progress in science and in other areas of our knowledge — Professor Christopher Hookway
to consider (something) unlikely
(+ whether/that) to consider (something) unlikely
I doubt whether she'll accept our offer
to distrust or lack confidence in (somebody)
find myself doubting him even when I know that he is honest — H L Mencken
to fear or suspect (something)
I doubt some foul play — Shakespeare
to be uncertain
doubtable adj
doubter noun
doubtingly adv
Middle English douten to fear, be uncertain, via Old French from Latin dubitare to doubt, from dubius: see dubious. The b was introduced in the 14th or 15th cent. to conform with Latin dubitare, but has never been pronounced: compare debt