1. (v. i.) To waver in opinion or judgment; to be in uncertainty as to belief respecting anything; to hesitate in belief; to be undecided as to the truth of the negative or the affirmative proposition; to b e undetermined.
2. (v. i.) To suspect; to fear; to be apprehensive.
3. (v. t.) To question or hold questionable; to withhold assent to; to hesitate to believe, or to be inclined not to believe; to withhold confidence from; to distrust; as, I have heard the story, but I doubt the truth of it.
4. (v. t.) To suspect; to fear; to be apprehensive of.
5. (v. t.) To fill with fear; to affright.
6. (n.) A fluctuation of mind arising from defect of knowledge or evidence; uncertainty of judgment or mind; unsettled state of opinion concerning the reality of an event, or the truth of an assertion, etc.; hesitation.
7. (v. i.) Uncertainty of condition.
8. (v. i.) Suspicion; fear; apprehension; dread.
9. (v. i.) Difficulty expressed or urged for solution; point unsettled; objection.
Thesaurus Entries
Humism, Pyrrhonism, agnosticism, agonize over, all-overs, anxiety, apprehension, apprehensiveness, awake a doubt, be at sea, be diffident, be doubtful, be dubious, be possessive, be skeptical, be uncertain, beat about, call in question, challenge, concern, confutability, contest, contestability, controvertibility, deniability, diffidence, disbelief, disbelieve, discredit, disputability, dispute, disquiet, distrust, distrustfulness, doubtful, doubtfulness, dubiety, dubiousness, dubitancy, fear, feel unsure, flounder, fluctuate, foreboding, greet with skepticism, grope, half believe, half-belief, harbor suspicions, have reservations, hesitate, hesitation, in doubt, incertitude, incredulity, irresolution, leeriness, misdoubt, misgive, misgiving, mistrust, mistrustfulness, puzzle over, qualm, qualmishness, query, question, questionableness, raise a question, refutability, reservations, scepticism, scoff, scoffing, scruple, scrupulousness, self-doubt, shadow of doubt, skepticalness, skepticism, smell a rat, suspect, suspicion, suspiciousness, thrash about, throw doubt upon, total skepticism, treat with reserve, unbelief, uncertainty, vacillate, wariness, waver, wonder, wonder whether, worry
