Synonyms of mainline

1 Syllable

first, head, main, key, chief, star, arch

2 Syllables

prime, crowning, highest, champion, peerless, major, stellar, matchless, strongest, leading, premier, greatest

3 Syllables

outstanding, principal, preeminent, controlling, prevailing, transcendent, capital, maximum, supreme, superior, principals, mainlined, paramount, essential, sovereign, cardinal, prominent, primary, foremost, mainlining, dominant

4 Syllables

predominant, second-to-none, unequaled, unrivaled

5 Syllables

incomparable, supereminent, unapproachable, unparalleled, super-eminent