Synonyms|312Antonyms|117|Broader|4Narrower|13Related|364
1
unfamiliar
1
unforced
1
unhackneyed
1
unheard-of
1
unimportant
1
unknown
1
unneeded
1
unprecedented
1
unprescribed
1
unrequired(adjective, optional)
1
unrestrictive
1
unusual
1
unwanted
1
volitional
1
voluntarily(adverb, unintentionally, optionally)
1
willful
1
willing
1
witting
0
avoidable
0
absorbing
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APASmart Define. (2015). obligatory thesaurus. Retrieved September 27, 2026, from https://smartdefine.org/obligatory/thesaurus/antonyms
ChicagoSmart Define. 2015. "obligatory thesaurus" https://smartdefine.org/obligatory/thesaurus/antonyms (accessed September 27, 2026).
HarvardSmart Define 2015, obligatory thesaurus, Smart Define, viewed 27 September, 2026, <https://smartdefine.org/obligatory/thesaurus/antonyms>.
MLASmart Define. "obligatory thesaurus" 14 April 2015. Web. 27 September 2026. <https://smartdefine.org/obligatory/thesaurus/antonyms>