Synonyms for plain

apparent, bare, basic, clear, definite, direct, down-to-earth, evident, explicit, known, lucid, modest, obvious, ordinary, overt, pellucid, perspicuous, pure, readable, self-evident, simple, stark, straightforward, transparent, unadorned, unambiguous, uncomplicated, undecorated, understandable, unembellished, unequivocal, unmistakable, unostentatious, unpretentious, unshowy