principal

1 coming before all others in importance our principal reason for coming here today Synonyms arch, big, capital, cardinal, central, chief, dominant, first, grand, great, greatest, highest, key, leading, main, master, number one (also No. 1), numero uno, overbearing, overmastering, overriding, paramount, predominant, preeminent, premier, primal, primary, foremost, prior, sovereign (also sovran), supremeRelated Words distinguished, eminent, illustrious, noble, notable, noteworthy, outstanding, prestigious, signal, star, stellar, superior; high-level, senior, top; important, influential, major, mighty, momentous, significant; incomparable, matchless, unequaled (or unequalled), unparalleled, unsurpassed; celebrated, famed, famous, renownedNear Antonyms inconsequential, inconsiderable, insignificant, minor, negligible, slight, trifling, trivial, unimportant; collateral, inferior, secondary, subordinate, subsidiaryAntonyms last, least

2 highest in rank or authority the principal researcher in the company's chemical division Synonyms chief, commanding, first, foremost, high, lead, leading, preeminent, premier, presiding, primary, prime, head, supereminent, supreme, topRelated Words high-level, senior; controlling, directing, managing, officiating, overseeing, regnant, reigning, ruling, supervisory; main, major, paramount, predominant, predominate, sovereign (also sovran); ascendant (also ascendent), dominant, grand, superior, topmost, upmost, upper, uppermostNear Antonyms ancillary, inferior, last, less, lesser, lower, lowly, second, secondary, subordinate, subsidiary; assistant, assisting, coadjutor, deputy, junior, under