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Dictionary.com
Definitions

no doubt

ADVERB
easily
Synonyms
STRONGEST
actually certainly clearly definitely probably really surely
WEAK
absolutely almost certainly assuredly beyond question by far decidedly doubtless doubtlessly far and away indeed indisputably indubitably plainly positively truly undeniably undoubtedly unequivocally unquestionably
Antonyms
STRONGEST
doubtfully dubiously indefinitely questionably
WEAK
difficultly doubtedly dubitably
ADVERB
for sure
Synonyms
WEAK
certainly dead sure definitely for a fact for certain for real no question no two ways about it really surely unquestionably
ADVERB
likely
Synonyms
STRONGEST
presumably
WEAK
assumably doubtless doubtlessly in all likelihood in all probability like as not most likely presumptively prima facie seemingly to all appearances
Antonyms
WEAK
improbably unlikely
ADVERB
necessarily
Synonyms
STRONGEST
automatically naturally undoubtedly unquestionably
WEAK
accordingly as a matter of course axiomatically beyond one's control by definition by its own nature cardinally come what may compulsorily consequently exigently from within fundamentally incontrovertibly indubitably ineluctably inescapably inexorably irresistibly of course of necessity perforce positively pressingly significantly unpreventably vitally willy-nilly without fail
Antonyms
STRONGEST
doubtfully questionably
WEAK
unnecessarily
ADVERB
probably
Synonyms
STRONGEST
apparently doubtless perhaps possibly presumably seemingly
STRONG
believably plausibly
WEAK
as likely as not as the case may be assumably dollars to doughnuts expediently feasibly imaginably in all likelihood in all probability like enough maybe most likely one can assume perchance practicably presumptively reasonably to all appearances
Antonyms
STRONGEST
improbably uncertain unlikely

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

“There was no doubt about that,” one said, noting that thousands of votes were likely at stake.

From Salon • May 6, 2026

There is no doubt that most of the holding was before the ball was kicked.

From BBC • May 5, 2026

Your husband is fortunate to have you and, no doubt, you are fortunate to have him.

From MarketWatch • May 1, 2026

I have no doubt that my listening experience was enhanced by having read “Nocturnes.”

From The Wall Street Journal • Apr. 29, 2026

“You’re strong,” she said with no doubt in her voice.

From "I Survived Hurricane Katrina, 2005" by Lauren Tarshis