Synonyms of first

1 Syllable
top, head, arch, front, key, chief, best, forth, least
2 Syllables
former, prime, ahead, special, kickoff, topflight, firstborn, topmost, oldest, besting, basic, archer, slightest, premier, topper, fronter, winners, champion, victor, vanward, primal, whilom, short-end, braggest, winner, older, loftiest, early, maiden, pioneer, leading, chiefest, smallest, headmost, victors, tester, first-born, first-hand, grass-roots, grassroots, taintless
3 Syllables
advanced, advance, pristine, germinal, principals, paramount, primeval, incipient, vanquisher, untapped, high-ranking, primordial, initial, cardinal, anterior, principal, capitals, supreme, primary, medalist, dominant, capital, mainline, substratal, beginning, savage, exalted, opening, excellent, defeater, unspotted
4 Syllables
foundational, underived, prize-winning, primogenial, title-holder, original, medalwinner, prizewinner, incipiently, highest-ranking, antecedent, microcosmic, undebased, unsurpassed, inceptive, prototype, initially, overweighing, immediate, prizewinners, primitive, originals, second-to-none, inaugural, unevolved, fundamental, preferably, substrative, subjugator, unpolluted
5 Syllables
super-eminent, meat-and-potatoes, exploratory, originally, preliminary, rudimentary, primitively, aboriginal, initiatory, elementary, overbalancing, supereminent, introductory, axiological
6 Syllables
underivative, alternatively