11
uppermost(adjective, excellent, lead, important, rank)
10
chieftain(noun, guide, head, boss, leader)
10
dean(noun, person, head, master, leader)
10
executive(noun, adjective, rank, master, post)
10
overriding(adjective, serious, basic, prime, supreme)
10
president(noun, guide, head, master, boss)
10
vital(adjective, body, great, importance, material)
9
captain(noun, guide, head, master, boss)
9
chairman(noun, authority, director)
9
elementary(adjective, important, significant, original, essential)
9
governor(noun, control, manage, guide, head)
9
headmaster(noun, master, dean)
9
kingpin(noun, master)
9
manager(noun, guide, head, master, boss)
9
pivotal(adjective, important, serious, basic, prime)
9
protagonist(noun, person, advance, start, character)
9
senior(noun, adjective, rank, master, post)
9
significant(adjective, good, great, big, important)
9
staple(adjective, lead, head, master, whole)
9
supervisor(noun, head, boss, leader, chief)
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APASmart Define. (2016). principal thesaurus. Retrieved September 25, 2026, from https://smartdefine.org/principal/thesaurus/synonyms
ChicagoSmart Define. 2016. "principal thesaurus" https://smartdefine.org/principal/thesaurus/synonyms (accessed September 25, 2026).
HarvardSmart Define 2016, principal thesaurus, Smart Define, viewed 25 September, 2026, <https://smartdefine.org/principal/thesaurus/synonyms>.
MLASmart Define. "principal thesaurus" 29 March 2016. Web. 25 September 2026. <https://smartdefine.org/principal/thesaurus/synonyms>