Antonyms for doubtful

Grammar : Adj

Spell : dout-fuhl

Phonetic Transcription : ˈdaʊt fəl

Definition of doubtful

Origin : late 14c., from doubt (n.) + -ful. Related: Doubtfully; doubtfulness.

adj questionable, unclear
adj not believing

Example sentences :

In the broad pathways of the ocean such a chance is doubtful.
Extract from : « Brave and Bold » by Horatio Alger

And, if we do, it is doubtful if we can attract their attention.
Extract from : « Brave and Bold » by Horatio Alger

My errors, however, have at least made me cautious and doubtful of my own conclusions.
Extract from : « 'Tis Sixty Years Since » by Charles Francis Adams

It is doubtful if it was mentally prepared to entertain it, or evolve the idea.
Extract from : « The Conquest of Fear » by Basil King

It is doubtful if many of the others were any better off in this respect.
Extract from : « Ester Ried Yet Speaking » by Isabella Alden

It is doubtful if she would have realized its significance, had she seen it.
Extract from : « K » by Mary Roberts Rinehart

And it is doubtful if the Street would have been greatly concerned even had it known.
Extract from : « K » by Mary Roberts Rinehart

It is doubtful if his mind quite grasped the situation, even.
Extract from : « Thoroughbreds » by W. A. Fraser

It is doubtful if any of the higher rated motors have greater efficiency.
Extract from : « Flying Machines » by W.J. Jackman and Thos. H. Russell

The first one paused, doubtful which of the two dangers to choose.
Extract from : « A Woman Tenderfoot » by Grace Gallatin Seton-Thompson

Synonyms for doubtful

Based on : Thesaurus.com - Gutenberg.org - Dictionary.com - Random House Unabridged Dictionary, © Random House, Inc. 2019