7
deponent(noun, law, person, witness, proof)
6
witness(noun, law, person, proof, observer)
5
deposer
4
attester(noun, law, person, witness)
4
informant
4
voucher
3
attestant(noun, law, person, witness, proof)
3
bystander(noun, witness, proof, testimony, observer)
3
eyewitness(noun, witness, proof, testimony, observer)
3
informer
3
spectator(noun, witness, proof, testimony, observer)
2
certifier
2
confirmer
2
declarer
2
witnesser
1
affirmer
1
attestor(noun, witness, proof, testimony, observer)
1
avower
1
beholder(noun, witness, proof, testimony, observer)
1
corroborator(noun, witness, proof, testimony, observer)
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APASmart Define. (2015). testifier thesaurus. Retrieved September 20, 2026, from https://smartdefine.org/testifier/thesaurus/synonyms
ChicagoSmart Define. 2015. "testifier thesaurus" https://smartdefine.org/testifier/thesaurus/synonyms (accessed September 20, 2026).
HarvardSmart Define 2015, testifier thesaurus, Smart Define, viewed 20 September, 2026, <https://smartdefine.org/testifier/thesaurus/synonyms>.
MLASmart Define. "testifier thesaurus" 10 April 2015. Web. 20 September 2026. <https://smartdefine.org/testifier/thesaurus/synonyms>