75 entries under extra topic. ×

22
increase(noun, verb, support, take, cover)
20
addition(noun, part, increase, delay, rise)
15
addendum(noun, act, increase, delay, development)
15
complement(noun, verb, part, increase, complete)
14
appendix(noun, increase, delay, development, spread)
12
extension(noun, part, increase, line, spread)
11
continuation(noun, increase, delay, development, line)
11
accessory(noun, part, increase, addition)
10
adjunct(noun, act, part, help, increase)
10
appendage(noun, part, increase, delay, development)
10
appurtenance(noun, part, increase, addition)
9
increment(noun, increase, gain, rise)
8
annex(noun, verb, part, advance, increase)
8
sequel(noun, increase, line, addition)
7
postscript(noun, increase, line, addition)
7
subsidiary(noun, increase, addition, extension)
6
augmentation(noun, increase, delay, rise, influence)
6
codicil(noun, act, part, increase, measure)
5
accession(noun, increase, raise, rise)
5
add-on(noun, increase, addition, attachment)
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APASmart Define. (2015). supplement thesaurus. Retrieved September 21, 2026, from https://smartdefine.org/supplement/thesaurus/synonyms
ChicagoSmart Define. 2015. "supplement thesaurus" https://smartdefine.org/supplement/thesaurus/synonyms (accessed September 21, 2026).
HarvardSmart Define 2015, supplement thesaurus, Smart Define, viewed 21 September, 2026, <https://smartdefine.org/supplement/thesaurus/synonyms>.
MLASmart Define. "supplement thesaurus" 22 December 2015. Web. 21 September 2026. <https://smartdefine.org/supplement/thesaurus/synonyms>