75 entries under primary topic. ×

13
primal(adjective, pure, primeval)
12
first(adjective, order, violent, important, opening)
12
original(adjective, characteristic, body, simple, plain)
11
indispensable(adjective, characteristic, important, significant, natural)
11
requisite(noun, adjective, important, need, significant)
10
important(adjective, significant, original, essential, critical)
9
bottom(noun, adjective, cause, start, base)
9
primitive(adjective, body, simple, plain, material)
9
primordial(adjective, violent, important, head, beginning)
8
foundational(adjective, clear, simple, plain, pure)
7
chief(adjective, important, significant, essential, basic)
7
initial(adjective, start, simple, plain, head)
7
paramount(adjective, important, significant, original, essential)
7
significant(adjective, important, original, essential, critical)
6
major(adjective, important, significant, original, essential)
5
leading(adjective, important, head, significant, beginning)
4
axiomatic(adjective, important, original, basic)
4
capital(adjective, important, essential, prime, vital)
4
dominant(adjective, top, important, significant, usual)
4
supporting(adjective, support, important, original, basic)
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APASmart Define. (2016). fundamental thesaurus. Retrieved September 25, 2026, from https://smartdefine.org/fundamental/thesaurus/synonyms
ChicagoSmart Define. 2016. "fundamental thesaurus" https://smartdefine.org/fundamental/thesaurus/synonyms (accessed September 25, 2026).
HarvardSmart Define 2016, fundamental thesaurus, Smart Define, viewed 25 September, 2026, <https://smartdefine.org/fundamental/thesaurus/synonyms>.
MLASmart Define. "fundamental thesaurus" 29 March 2016. Web. 25 September 2026. <https://smartdefine.org/fundamental/thesaurus/synonyms>