- (a.) Fearful; apprehensive; suspicious.
- (a.) Not settled in opinion; undetermined; wavering; hesitating in belief; also used, metaphorically, of the body when its action is affected by such a state of mind; as, we are doubtful of a fact or of the propriety of a measure.
- (a.) Characterized by ambiguity; dubious; as, a doubtful expression; a doubtful phrase.
- (a.) Of uncertain issue or event.
- (a.) Admitting of doubt; not obvious, clear or certain; questionable; not decided; not easy to be defined, classed or named; as, a doubtful case, hue, claim, title, species, and the like.
Webster's Revised Unabridged Dictionary
| APA | Webster's. (2011). doubtful. Retrieved September 23, 2026, from http://smartdefine.org/doubtful/definitions/2000184 |
| Chicago | Webster's. 2011. "doubtful" http://smartdefine.org/doubtful/definitions/2000184 (accessed September 23, 2026). |
| Harvard | Webster's 2011, doubtful, Smart Define, viewed 23 September, 2026, <http://smartdefine.org/doubtful/definitions/2000184>. |
| MLA | Webster's. "doubtful" 27 May 2011. Web. 23 September 2026. <http://smartdefine.org/doubtful/definitions/2000184> |