doubt > define

noun

• The state of being unsure of something.
  • synonyms: uncertainty, incertitude, dubiety, doubtfulness, dubiousness
• Uncertainty about the truth or factuality or existence of something.
  • usage: "the dubiousness of his claim"; "there is no question about the validity of the enterprise"
  • synonyms: dubiousness, doubtfulness, question

verb

• Consider unlikely or have doubts about.
  • usage: "I doubt that she will accept his proposal of marriage"
• Lack confidence in or have doubts about.
  • usage: "I doubt these reports"; "I suspect her true motives"; "she distrusts her stepmother"

• (v.t.) To suspect; to fear; to be apprehensive of.
• (v.i.) To suspect; to fear; to be apprehensive.
• (v.i.) Suspicion; fear; apprehension; dread.
• (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.
• (v.i.) Difficulty expressed or urged for solution; point unsettled; objection.
• (v.i.) Uncertainty of condition.
• (v.t.) To fill with fear; to affright.
• (v.i.) 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.
• (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.