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Definitions

guarantee

[gar-uhn-tee] / ˌgær ənˈti /
NOUN
pledge, promise
Synonyms
STRONGEST
agreement assurance certificate collateral contract deposit insurance security warranty
STRONG
attestation bail bargain bond certainty certification charter covenant earnest gage guaranty lock oath pawn pipe recognizance surety testament token undertaking vow warrant word
WEAK
sure thing word of honor
Antonyms
STRONGEST
disagreement uncertainty
STRONG
breach break
VERB
pledge, promise
Synonyms
STRONGEST
assure ensure insure maintain protect prove secure support
STRONG
affirm angel attest aver back bankroll certify confirm cosign endorse evidence evince grubstake guaranty juice mortgage reassure stake swear testify wager warrant witness
WEAK
answer for be surety for bind oneself get behind give bond make bail make certain make sure pick up the check pick up the tab sign for stand behind stand up for vouch for
Antonyms
STRONGEST
harm hurt injure let go neglect
STRONG
contradict deny discourage disprove invalidate oppose refute reject repudiate veto
WEAK
break

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.

As part of the deal, Moderna has agreed to guarantee fast and affordable supply of the vaccine to low and middle-income countries in any future pandemic.

From BBC • Apr. 21, 2026

But the national association of mobile network operators said on Monday that they can no longer guarantee uninterrupted services, citing fuel shortages.

From Barron's • Apr. 21, 2026

The military wanted to guarantee a reliable domestic supply of a critical computer chip.

From The Wall Street Journal • Apr. 20, 2026

I guarantee it would be money well spent.

From Los Angeles Times • Apr. 18, 2026

He just sent a couple of texts to guarantee that he keeps them.

From "On the Come Up" by Angie Thomas

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