Word: plainest

obvious, clear, crystal clear, evident, apparent, manifest, patent, discernible, perceptible, noticeable, recognizable, unmistakable, transparent, pronounced, marked, striking, conspicuous, self-evident, indisputable, writ large, standing/sticking out like a sore thumb, intelligible, comprehensible, understandable, coherent, uncomplicated, lucid, unambiguous, simple, straightforward, user-friendly, perspicuous, candid, frank, outspoken, forthright, direct, honest, truthful, blunt, bald, explicit, unequivocal, upfront, ordinary, unadorned, unembellished, unornamented, unostentatious, unfussy, basic, modest, unsophisticated, without frills, homespun, restrained, unshowy, unflashy, muted, everyday, workaday, homely, unattractive, unprepossessing, ugly, ill-favored, unlovely, not much to look at, sheer, pure, downright, out-and-out, unmitigated, unmixed, unmingled, unpatterned, unvarnished, spare, bare