200 entries under adjective topic. ×

5
quintessential(essential, required, needed)
4
all-important(essential, required, needed)
4
automatic
4
basal(body, material, important, significant)
4
expedient(essential, required, wanted, needed)
4
inerrant(certain, inevitable)
4
inevasible(certain, obvious, inevitable, inescapable)
4
logical(clear, sound, reasonable, rational)
4
of the essence(expression, idiom, important, essential)
4
underlying(important, significant, original, essential)
3
absolute
3
bottom-line(important, significant, original, essential)
3
called-for(important, serious, essential, critical)
3
consequential(important, prominent, exalted)
3
elemental(body, material, important, significant)
3
high(important, prominent, exalted)
3
influential(great, big, important, significant)
3
intrinsic(important, significant, original, essential)
3
primitive(body, material, important, significant)
3
serious(big, important, significant, substantial)
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APASmart Define. (2015). necessary thesaurus. Retrieved September 25, 2026, from https://smartdefine.org/necessary/thesaurus/synonyms
ChicagoSmart Define. 2015. "necessary thesaurus" https://smartdefine.org/necessary/thesaurus/synonyms (accessed September 25, 2026).
HarvardSmart Define 2015, necessary thesaurus, Smart Define, viewed 25 September, 2026, <https://smartdefine.org/necessary/thesaurus/synonyms>.
MLASmart Define. "necessary thesaurus" 2 November 2015. Web. 25 September 2026. <https://smartdefine.org/necessary/thesaurus/synonyms>