4
heavily(adverb, heavily)
4
intrinsically(adverb, intrinsicality)
4
mainly
4
mostly
4
probably
4
really
4
sincerely
4
solidly(adverb, solidly)
3
altogether
3
amply
3
approximately(adverb, near, really, much, roughly)
3
au fond(expression, idiom, intrinsicality)
3
concretely(adverb, solidly)
3
corporeally(adverb, materially)
3
easily
3
first and foremost
3
fundamentally
3
good
3
grandly
3
in fact(expression, idiom, adverb)
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APASmart Define. (2015). substantially thesaurus. Retrieved September 22, 2026, from https://smartdefine.org/substantially/thesaurus/synonyms
ChicagoSmart Define. 2015. "substantially thesaurus" https://smartdefine.org/substantially/thesaurus/synonyms (accessed September 22, 2026).
HarvardSmart Define 2015, substantially thesaurus, Smart Define, viewed 22 September, 2026, <https://smartdefine.org/substantially/thesaurus/synonyms>.
MLASmart Define. "substantially thesaurus" 14 April 2015. Web. 22 September 2026. <https://smartdefine.org/substantially/thesaurus/synonyms>