6
span(noun, territory, order, time, area)
6
spreading(noun, expansion)
5
accretion(noun, increase, raise, gain, rise)
5
accrual(noun, increase, raise, gain, rise)
5
advancement(noun, advance, increase, progress, development)
5
appurtenance(noun, part, extra, addition, decoration)
5
dilatation(noun, increase, spread, growth, addition)
5
dispersion(noun, increase, expansion, circulation, spreading)
5
ell(noun, division, section, addition, annex)
5
fixture(noun, part, extra, addition, accessory)
5
length(noun, territory, order, area, remove)
5
persistence(noun, endurance, stability, continuation, steadiness)
5
radius(noun, territory, order, area, increase)
5
swell(noun, advance, raise, gain, rise)
5
telephone extension(noun, expression, idiom)
4
accompaniment(noun, addition, decoration, accompaniment, fixture)
4
add-on(noun, increase, treat, extra, extravagance)
4
ascent
4
breadth(noun, time, area, increase, remove)
4
burgeoning(noun, raise, gain, rise, development)
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APASmart Define. (2015). extension thesaurus. Retrieved September 22, 2026, from https://smartdefine.org/extension/thesaurus/synonyms
ChicagoSmart Define. 2015. "extension thesaurus" https://smartdefine.org/extension/thesaurus/synonyms (accessed September 22, 2026).
HarvardSmart Define 2015, extension thesaurus, Smart Define, viewed 22 September, 2026, <https://smartdefine.org/extension/thesaurus/synonyms>.
MLASmart Define. "extension thesaurus" 22 December 2015. Web. 22 September 2026. <https://smartdefine.org/extension/thesaurus/synonyms>