365 entries under adjective topic. ×

13
inherent(natural, essential, basic, innate)
13
main(important, significant, usual, essential)
13
primal(pure, primary, primeval)
12
first(order, violent, important, opening)
12
original(characteristic, body, simple, plain)
11
indispensable(characteristic, important, significant, natural)
11
requisite(noun, important, need, significant)
11
simple(top, pure, straightforward, whole)
10
base(noun, support, regulation, action)
10
important(significant, original, essential, critical)
9
bottom(noun, cause, start, base)
9
constitutional(important, natural, essential, basic)
9
primitive(body, simple, plain, material)
9
primordial(violent, important, head, beginning)
8
component(noun, drop, part, material)
8
constituent(noun, drop, part, material)
8
critical(severe, important, significant, original)
8
foundational(clear, simple, plain, pure)
8
ingrained(intrinsicality, intrinsic)
8
natural(characteristic, simple, material, essential)
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APASmart Define. (2016). fundamental thesaurus. Retrieved September 26, 2026, from https://smartdefine.org/fundamental/thesaurus/synonyms
ChicagoSmart Define. 2016. "fundamental thesaurus" https://smartdefine.org/fundamental/thesaurus/synonyms (accessed September 26, 2026).
HarvardSmart Define 2016, fundamental thesaurus, Smart Define, viewed 26 September, 2026, <https://smartdefine.org/fundamental/thesaurus/synonyms>.
MLASmart Define. "fundamental thesaurus" 29 March 2016. Web. 26 September 2026. <https://smartdefine.org/fundamental/thesaurus/synonyms>