2
give the nod(expression, idiom, support, praise, favor)
2
illustrate(verb, evince)
2
indicate(verb, state, show, sign, display)
2
make legal(noun, expression, endorse, prove, verify)
2
okay(verb, support, state, praise, favor)
2
reinforce(substantiate, corroborate)
2
rubber-stamp(verb, support, state, praise, favor)
2
rubber stamp(expression, approve, sanction, endorse, validate)
2
say amen to(verb, expression, idiom, sign)
2
second(verb, support, favor, back, approve)
2
sign off on(expression, idiom, support, back, sign)
2
subscribe(verb, support, back, sign, explain)
2
subscribe to(verb, expression, support, praise, favor)
2
test(verb, show, determine, display, idea)
2
underpin(verb, support, back, sign, explain)
2
undersign(verb, sign)
1
John Hancock(expression, endorse, prove, verify, substantiate)
1
add up(verb, expression, show, determine, confirm)
1
amen
1
approbate(verb, approve)
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APASmart Define. (2015). authenticate thesaurus. Retrieved September 20, 2026, from https://smartdefine.org/authenticate/thesaurus/synonyms
ChicagoSmart Define. 2015. "authenticate thesaurus" https://smartdefine.org/authenticate/thesaurus/synonyms (accessed September 20, 2026).
HarvardSmart Define 2015, authenticate thesaurus, Smart Define, viewed 20 September, 2026, <https://smartdefine.org/authenticate/thesaurus/synonyms>.
MLASmart Define. "authenticate thesaurus" 10 April 2015. Web. 20 September 2026. <https://smartdefine.org/authenticate/thesaurus/synonyms>