24
fast(adjective, calm, strong, secure, tough)
24
weighty(adjective, good, strong, sound, right)
23
robust(adjective, strong, sound, complete, tough)
22
affluent(adjective, easy, rich, large, robust)
22
consequential(adjective, importance, big, heavy, important)
22
great(adjective, importance, valuable, main, notable)
22
steadfast(adjective, calm, strong, secure, strain)
22
sturdy(adjective, calm, strong, hard, sound)
21
enduring(adjective, calm, strong, sound, secure)
21
important(adjective, strong, importance, big, heavy)
21
lasting(adjective, strain, firmness, labour, hardiness)
21
tangible(adjective, body, solid, physical, material)
21
well-established(adjective, strain, firmness, labour, hardiness)
20
concrete(adjective, body, hard, tough, solid)
20
constant(adjective, calm, strong, secure, tough)
20
impregnable(adjective, strain, firmness, labour, hardiness)
20
permanent(adjective, strain, firmness, labour, hardiness)
20
refractory(adjective, strain, firmness, labour, hardiness)
20
rock-solid(adjective, hard, strain, firmness, compact)
19
actual(adjective, solid, physical, material, real)
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APASmart Define. (2016). substantial thesaurus. Retrieved September 23, 2026, from https://smartdefine.org/substantial/thesaurus/synonyms
ChicagoSmart Define. 2016. "substantial thesaurus" https://smartdefine.org/substantial/thesaurus/synonyms (accessed September 23, 2026).
HarvardSmart Define 2016, substantial thesaurus, Smart Define, viewed 23 September, 2026, <https://smartdefine.org/substantial/thesaurus/synonyms>.
MLASmart Define. "substantial thesaurus" 24 March 2016. Web. 23 September 2026. <https://smartdefine.org/substantial/thesaurus/synonyms>