12
broadening(noun, increase, spread, growth, addition)
12
extent(noun, territory, order, time, area)
12
progression(noun, advance, progress, development, endurance)
11
adjunct(noun, part, increase, spread, extra)
11
appendage(noun, part, increase, spread, extra)
11
elongation(noun, act, increase, spread, growth)
11
swing(noun, territory, order, run, kind)
10
dilation(noun, expansion, circulation, spreading, distention)
10
increment(noun, increase, raise, rise, growth)
10
scope(noun, territory, time, area, increase)
9
annexe
9
appendix(noun, increase, spread, extra, addition)
9
course(noun, development, evolution, breakthrough)
9
cultivation(noun, advance, progress, development, growth)
9
elaboration(noun, raise, gain, rise, development)
9
evolvement(noun, advance, progress, development, growth)
9
expanse(noun, territory, order, time, area)
9
inflation(noun, increase, raise, gain, rise)
9
reach(noun, territory, time, area, increase)
9
sequel(noun, increase, development, extra, result)
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APASmart Define. (2015). extension thesaurus. Retrieved September 21, 2026, from https://smartdefine.org/extension/thesaurus/synonyms
ChicagoSmart Define. 2015. "extension thesaurus" https://smartdefine.org/extension/thesaurus/synonyms (accessed September 21, 2026).
HarvardSmart Define 2015, extension thesaurus, Smart Define, viewed 21 September, 2026, <https://smartdefine.org/extension/thesaurus/synonyms>.
MLASmart Define. "extension thesaurus" 22 December 2015. Web. 21 September 2026. <https://smartdefine.org/extension/thesaurus/synonyms>