13
leftover(adjective, waste, split, spare, extreme)
13
luxury(noun, adjective, comfort, treat, extravagance)
13
redundant(adjective, spare, unreasonable, extreme, useless)
11
ancillary(noun, adjective, support, spare, inferior)
11
special(adjective, spare, excess, further, alternative)
10
adjunct(noun, part, increase, addition, extension)
10
extraneous(adjective, spare, excess, further, surplus)
10
extremely(adjective, adverb, big, property, really)
10
free(adjective, open, reserve, busy, replacement)
10
new(adjective, increase, spare, excess, further)
10
particularly(adverb, separate, single, alone, apart)
10
reserve(noun, adjective, support, lower, spare)
9
addendum(noun, increase, addition, accessory, attachment)
9
attachment(noun, addition, accessory, decoration, supplement)
9
supererogatory(adjective, spare, extreme, reserve, useless)
8
also(adjective, new, spare, addition, additional)
8
another(adjective, place, lower, new, spare)
8
dividend(noun, prize, advantage, share, stock)
8
exceptionally(adverb, big, really, extremely, particularly)
8
other(adjective, place, increase, lower, new)
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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>