104 entries under addition topic. ×

30
additional(adjective, place, increase, lower, new)
23
spare(noun, verb, adjective, adverb, support)
20
supplementary(adjective, support, new, spare, excess)
20
further(adjective, adverb, increase, new, spare)
19
accessory(noun, adjective, support, part, lower)
19
auxiliary(noun, adjective, support, part, lower)
18
supernumerary(noun, adjective, spare, extreme, reserve)
17
more(adjective, adverb, increase, new, spare)
16
supplemental(adjective, spare, excess, further)
15
plus(noun, adjective, adverb, spare, advantage)
14
added(noun, adjective, increase, new, spare)
13
bonus(noun, adjective, gain, benefit, advantage)
13
luxury(noun, adjective, comfort, treat, extravagance)
11
ancillary(noun, adjective, support, spare, inferior)
10
adjunct(noun, part, increase, extension)
9
addendum(noun, increase, accessory, attachment)
9
attachment(noun, accessory, decoration, supplement)
8
also(adjective, new, spare, additional)
8
supplement(noun, part, increase, extension)
7
appendage(noun, part, increase, extension)
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APASmart Define. (2016). extra thesaurus. Retrieved September 22, 2026, from https://smartdefine.org/extra/thesaurus/synonyms
ChicagoSmart Define. 2016. "extra thesaurus" https://smartdefine.org/extra/thesaurus/synonyms (accessed September 22, 2026).
HarvardSmart Define 2016, extra thesaurus, Smart Define, viewed 22 September, 2026, <https://smartdefine.org/extra/thesaurus/synonyms>.
MLASmart Define. "extra thesaurus" 30 March 2016. Web. 22 September 2026. <https://smartdefine.org/extra/thesaurus/synonyms>