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Definitions

undeniably

ADVERB
beyond a shadow of a doubt
Synonyms
WEAK
absolutely beyond a doubt beyond any doubt beyond doubt categorically certainly clearly definitely indubitably no ifs ands or buts about it obviously unquestionably
ADVERB
clearly
Synonyms
STRONGEST
apparently certainly definitely distinctly evidently obviously openly plainly positively precisely seemingly surely undoubtedly
WEAK
acutely audibly beyond doubt conspicuously decidedly discernibly incontestably incontrovertibly indubitably lucidly manifestly markedly noticeably overtly patently penetratingly perceptibly prominently purely recognizably sharply sonorously translucently transparently unmistakably
Antonyms
STRONGEST
doubtfully dubiously equivocally questionably uncertain
WEAK
indefinitely indistinctly mysteriously vaguely
ADVERB
definitely
Synonyms
STRONGEST
absolutely clearly decidedly doubtless easily finally obviously plainly surely unequivocally unquestionably
WEAK
beyond any doubt categorically doubtlessly explicitly expressly far and away indubitably no ifs ands or buts about it positively specifically unmistakably without doubt without fail without question
Antonyms
STRONGEST
doubtedly doubtfully dubiously questionable questionably uncertain
WEAK
indefinitely
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 no doubt plainly positively truly undoubtedly unequivocally unquestionably
Antonyms
STRONGEST
doubtfully dubiously indefinitely questionably
WEAK
difficultly doubtedly dubitably
ADVERB
indeed
Synonyms
STRONGEST
absolutely certainly easily naturally really surely truly undoubtedly very very much
WEAK
amen doubtlessly even for real in point of fact in truth much of course positively strictly sure thing to be sure verily veritably well
Antonyms
STRONGEST
doubtfully dubiously indefinite questionably
ADVERB
obviously
Synonyms
STRONGEST
apparently certainly clearly definitely evidently noticeably plainly seemingly surely undoubtedly visibly
WEAK
distinctly incontestably of course openly unquestionably without doubt
Antonyms
STRONGEST
doubtfully dubiously equivocally indefinitely questionably uncertain vaguely
ADVERB
positively
Synonyms
STRONGEST
certainly easily emphatically firmly undoubtedly
WEAK
amen assuredly categorically doubtless doubtlessly flat flat out for a fact indubitably no catch no holds barred no ifs ands or buts no kicker no strings attached on the money on the nose really truly right on sure surely the ticket to a tee unequivocally unmistakably unquestionably with certainty without qualification
Antonyms
STRONGEST
doubtfully questionably
ADVERB
undoubtedly
Synonyms
STRONGEST
assuredly definitely doubtless easily indeed really surely truly unquestionably
WEAK
beyond question beyond shadow of a doubt of course unmistakably well without doubt
Antonyms
STRONGEST
doubtedly doubtfully dubiously questionably uncertain
WEAK
indefinite
ADVERB
unquestionably
Synonyms
STRONGEST
absolutely definitely surely undoubtedly
STRONG
decidedly emphatically unimpeachably
WEAK
assuredly certainly incontrovertibly indefensibly indubitably of course positively unequivocally
Antonyms
STRONGEST
doubtfully indefinite questionably
WEAK
dubiously

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.

NASA’s Artemis II astronauts are undeniably making history as they embark on the first crewed mission to the moon in over 50 years.

From Salon • Apr. 10, 2026

Geese have undeniably been at the forefront of conversations on tantalizing, new rock and the revival of the classic “band scene.”

From Los Angeles Times • Apr. 9, 2026

It was not pretty, nor particularly elite, but it was undeniably entertaining.

From BBC • Apr. 4, 2026

Sunday was undeniably great theater, two bombastic blue chip programs, Final Four again on the line.

From The Wall Street Journal • Mar. 30, 2026

The silk is undeniably black and white, the transition between the two a soft fade of grey, distinct fibers visible in the weave.

From "The Night Circus" by Erin Morgenstern