8
rarely(adverb, property, very, really, extremely)
8
supplement(noun, part, increase, addition, extension)
8
uncommonly(adverb, property, little, really, hardly)
8
unnecessary(adjective, spare, unreasonable, extreme, useless)
7
perk(noun, adjective, gain, benefit, informal)
7
adventitious
7
appendage(noun, part, increase, addition, extension)
7
besides(adjective, adverb, new, spare, addition)
7
beyond(adjective, adverb, spare, excess, further)
7
especially(adverb, very, really, extremely, particularly)
7
frill(noun, treat, luxury, extravagance, addition)
7
non-essential(noun, adjective)
7
premium(noun, gain, prize, advantage, share)
7
subsidiary(noun, adjective, support, increase, lower)
7
supportive(adjective, spare, auxiliary)
7
tip(noun, adjective, spare, advantage, reward)
7
too(spare, extreme, addition, excessive, also)
7
unneeded(adjective, spare, extreme, useless, excess)
7
unusually(adverb, property, little, really, hardly)
6
adscititious(adjective, addition)
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APASmart Define. (2016). extra thesaurus. Retrieved September 21, 2026, from https://smartdefine.org/extra/thesaurus/synonyms
ChicagoSmart Define. 2016. "extra thesaurus" https://smartdefine.org/extra/thesaurus/synonyms (accessed September 21, 2026).
HarvardSmart Define 2016, extra thesaurus, Smart Define, viewed 21 September, 2026, <https://smartdefine.org/extra/thesaurus/synonyms>.
MLASmart Define. "extra thesaurus" 30 March 2016. Web. 21 September 2026. <https://smartdefine.org/extra/thesaurus/synonyms>