83 entries under primary topic. ×

15
basic(adjective, body, material, important, significant)
14
premier(adjective, order, top, excellent, lead)
13
central(adjective, lead, important, head, significant)
13
prominent(adjective, good, important, wonderful, famous)
13
supreme(adjective, order, bad, tough, top)
12
arch(noun, adjective, order, top, lead)
12
highest(adjective, order, bad, tough, top)
11
outstanding(adjective, bad, great, tough, top)
11
sovereign(noun, adjective, excellent, superior, important)
11
uppermost(adjective, excellent, lead, important, rank)
10
vital(adjective, body, great, importance, material)
9
elementary(adjective, important, significant, original, essential)
9
significant(adjective, good, great, big, important)
8
grand(adjective, lead, fine, important, head)
8
number one(noun, expression, adjective, order, bad)
8
preeminent(adjective, order, bad, great, tough)
8
ruling(adjective, excellent, superior, important, head)
8
stellar(adjective, great, tough, top, heavy)
7
greatest(adjective, bad, tough, top, excellent)
7
momentous(adjective, good, bad, great, excellent)
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APASmart Define. (2016). principal thesaurus. Retrieved September 26, 2026, from https://smartdefine.org/principal/thesaurus/synonyms
ChicagoSmart Define. 2016. "principal thesaurus" https://smartdefine.org/principal/thesaurus/synonyms (accessed September 26, 2026).
HarvardSmart Define 2016, principal thesaurus, Smart Define, viewed 26 September, 2026, <https://smartdefine.org/principal/thesaurus/synonyms>.
MLASmart Define. "principal thesaurus" 29 March 2016. Web. 26 September 2026. <https://smartdefine.org/principal/thesaurus/synonyms>