1
say amen to(verb, expression, idiom, phrasal verb, sign)
1
say so(verb, expression, support, maintain, back)
1
seal
1
secure(verb, support, maintain, protect, promise)
1
sign off on(verb, expression, idiom, phrasal verb, sign)
1
sign on dotted line(verb, expression, idiom, sign, underwrite)
1
signature(verb, support, take, favor, agree)
1
sponsor(verb, support, maintain, back, declare)
1
stake(verb, support, maintain, secure, protect)
1
stand behind(verb, expression, phrasal verb, support, maintain)
1
subscribe to
1
substantiate(verb, support, maintain, back, declare)
1
superscribe(verb, sign, underwrite, subscribe, authenticate)
1
swear(verb, support, maintain, secure, protect)
1
swear up and down(verb, expression, idiom, phrasal verb, support)
1
uphold(verb, support, maintain, back, declare)
1
validate
1
verify(verb, support, maintain, back, declare)
1
vouch(verb, give)
1
vouch for(verb, expression, phrasal verb, support, maintain)
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APASmart Define. (2015). cosign thesaurus. Retrieved September 22, 2026, from https://smartdefine.org/cosign/thesaurus/synonyms
ChicagoSmart Define. 2015. "cosign thesaurus" https://smartdefine.org/cosign/thesaurus/synonyms (accessed September 22, 2026).
HarvardSmart Define 2015, cosign thesaurus, Smart Define, viewed 22 September, 2026, <https://smartdefine.org/cosign/thesaurus/synonyms>.
MLASmart Define. "cosign thesaurus" 24 December 2015. Web. 22 September 2026. <https://smartdefine.org/cosign/thesaurus/synonyms>