1. doubtful - Noun
2. doubtful - Adjective
3. doubtful - Adjective Satellite
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.
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.
Characterized by ambiguity; dubious; as, a doubtful expression; a doubtful phrase.
Of uncertain issue or event.
Fearful; apprehensive; suspicious.
Source: Webster's dictionaryAll those instances to be found in history, whether real or fabulous, of a doubtful public spirit, at which morality is perplexed, reason is staggered, and from which affrighted Nature recoils, are their chosen and almost sole examples for the instruction of their youth. Edmund Burke
A civilized society is one which tolerates eccentricity to the point of doubtful sanity. Robert Frost
Necessity may render a doubtful act innocent, but it cannot make it praiseworthy. Joseph Joubert
Doubtful the die, and dire the cast. Persian Proverb
A patient that can swallow food makes the nurse doubtful. Madagascan Proverb
Even doubtful accusations leave a stain behind them. Danish Proverb