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Dictionary.com
Definitions

without fail

ADVERB
assuredly
Synonyms
STRONGEST
undoubtedly
WEAK
absolutely certainly definitely of course positively surely unquestionably
Antonyms
WEAK
doubtfully questionably
ADVERB
certainly
Synonyms
STRONGEST
absolutely assuredly exactly surely
WEAK
cert for a fact of course positively posolutely right on unquestionably
Antonyms
STRONGEST
doubtfully questionably
WEAK
dubiously equivocally
ADVERB
definitely
Synonyms
STRONGEST
absolutely clearly decidedly doubtless easily finally obviously plainly surely undeniably 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 question
Antonyms
STRONGEST
doubtedly doubtfully dubiously questionable questionably uncertain
WEAK
indefinitely
ADVERB
necessarily
Synonyms
STRONGEST
automatically naturally no doubt 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
Antonyms
STRONGEST
doubtfully questionably
WEAK
unnecessarily
ADVERB
OK
Synonyms
STRONGEST
fine okay
STRONG
affirmative amen good true yea
WEAK
absolutely agreed all right assuredly aye beyond a doubt by all means certainly definitely even so exactly gladly good enough granted indubitably just so most assuredly naturally of course positively precisely roger sure thing surely undoubtedly unquestionably very well willingly yep
ADVERB
right on
Synonyms
WEAK
absolutely affirmative agreed all right amen assuredly aye beyond a doubt by all means certainly definitely even so exactly fine gladly good good enough granted indubitably just so most assuredly naturally of course okay positively precisely roger sure thing surely true undoubtedly unquestionably very well willingly yea yep
ADVERB
roger
Synonyms
WEAK
absolutely affirmative agreed all right amen assuredly aye beyond a doubt by all means certainly definitely even so exactly fine gladly good good enough granted indubitably just so most assuredly naturally of course okay positively precisely sure thing surely true undoubtedly unquestionably very well willingly yea yep
ADVERB
surely
Synonyms
STRONGEST
absolutely assuredly certainly clearly definitely evidently indeed inevitably inexorably plainly undoubtedly unquestionably
WEAK
admittedly beyond doubt beyond shadow of doubt come what may conclusively decidedly distinctly doubtlessly explicitly fixedly for certain indubitably infallibly irrefutably manifestly nothing else but positively rain or shine to be sure unequivocally unerringly unfailingly unmistakably unshakably with certainty
Antonyms
STRONGEST
doubtfully dubiously indefinite indefinitely questionably vaguely
WEAK
uncertain
ADVERB
uh-huh
Synonyms
WEAK
absolutely affirmative agreed all right amen assuredly aye beyond a doubt by all means certainly definitely even so exactly fine gladly good good enough granted indubitably just so most assuredly naturally of course okay positively precisely roger sure thing surely true undoubtedly unquestionably very well willingly yea yep
ADVERB
yes
Synonyms
STRONG
affirmative amen fine good okay true yea
WEAK
all right aye beyond a doubt by all means certainly definitely even so exactly gladly good enough granted indubitably just so most assuredly naturally of course positively precisely sure thing surely undoubtedly unquestionably very well willingly yep
Antonyms
WEAK
disagreed

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.

"The biggest thing for me is that I now need to nap, every day, without fail," she says.

From BBC • Mar. 5, 2026

"Pretty much without fail every sceptical scientist that comes on board who gets to go on a dive changes their opinion."

From Barron's • Jan. 26, 2026

It’s not easy for NFL long snappers to stand out, their exacting trade hinging exclusively on repeating the same action without fail or fanfare.

From Los Angeles Times • Jun. 4, 2025

Assuming they saved $425 each month, and did so without fail, the renter would spend 199 months saving for a home.

From Salon • Mar. 9, 2025

Every single day, without fail, for over two years.”

From "We Were Here" by Matt De La Peña