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Definitions

cosign

[koh-sahyn, koh-sahyn] / ˈkoʊˌsaɪn, koʊˈsaɪn /
VERB
endorse
Synonyms
STRONGEST
sign
STRONG
authenticate autograph notarize subscribe superscribe undersign underwrite
WEAK
add one's name to put John Hancock on put signature on rubber-stamp say amen to sign off on sign on dotted line
Antonyms
WEAK
censure disapprove oppose protest reject repel unauthorize
VERB
guarantee
Synonyms
STRONGEST
assure ensure insure maintain protect prove secure support
STRONG
affirm angel attest aver back bankroll certify confirm 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
VERB
subscribe
Synonyms
STRONGEST
underwrite
STRONG
accede acquiesce advocate approve assent autograph back bless boost consent countenance ditto endorse favor ink obey okay sanction sign support take undersign
WEAK
get behind give stamp of approval give the go-ahead go along with hold with put John Hancock on rubber-stamp signature yes
Antonyms
STRONG
condemn deny disagree disallow disapprove discourage dissent hinder hurt object oppose prevent protest refuse reject veto
VERB
vouch
Synonyms
STRONG
affirm assert asseverate assure avert avow back certify confirm contend corroborate declare guarantee maintain okay predicate profess prove sponsor substantiate support testify uphold verify vow warrant witness
WEAK
act as a witness answer for attest to be responsible for bear testimony get behind give an affidavit put forth rubber-stamp say so sign for stand up for swear to swear up and down
Antonyms
STRONG
break condemn contradict deny desert disapprove disavow disclaim discourage discredit disprove invalidate neglect oppose refuse refute reject repudiate veto
WEAK
renounce

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.

However, the problem is that my husband, as a co-owner, is expected to cosign any loan his brother takes out for renovations.

From MarketWatch • Jan. 21, 2026

Unlike other players on the Cavaliers, LeBron James refused to cosign the letter, claiming that he did not have “enough information” on the subject.

From Salon • Apr. 20, 2024

But the dual release ignited a debate among country-music connoisseurs, many of whom refused to cosign the artist’s genre pivot.

From Los Angeles Times • Mar. 29, 2024

And Ja Rule is happy, as always, to cosign what’s to come: “So much Utility with this project it’s insane!!!” he tweeted.

From The Verge • Feb. 23, 2022

Not only that, but he would have to cosign them or they wouldn’t count.

From "Schooled" by Gordon Korman

Vocabulary lists containing cosign

Personal Finance and Financial Literacy - Introductory

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Personal Finance and Financial Literacy - High School

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Personal Finance and Financial Literacy - Middle School

Want to remember this word for good? Start your learning journey today with our library of interactive, themed word lists built by the experts at Vocabulary.com – we'll help you make the most of your study time!