Flat; level: smooth; even; free from elevations and depressions: as, a plain surface or country.Open; unobstructed by intervening barriers or defenses.Easy; free from intricacies or difficulties: as, plain exercises in shorthand.Undisguised; frank; sincere; unreserved.Clear; evident; manifest; easily perceived or understood: as, to make one's meaning plain; it was plain he was offended.Unqualified: undisguised; unmistakable; sheer; downright; absolute.Without a figured pattern; unornamented with decorative patterns or designs; also, when applied to fabrics, untwilled or uncolored: as. plain black cloth; plain muslin.Void of ornament or bright color; without embellishment; simple; unadorned.Without beauty; homely: as, she is plain, but clever.Artless; simple; unlearned; without artifice or affectation; unsophisticated.Not highly seasoned; not rich; not luxuriously dressed: as, a plain diet.Incomplex; simple.In card-playing, not trumps; lay: as, a plain card; a plain suit.Whole-colored; not variegated: as, plain white eggs.Smooth; unstriate, as muscular fiber.Embroidery in the same color as the ground.Clear, Evident, etc. (see manifest), distinct, patent, unmistakable, unequivocal, unambiguous, explicit, intelligible.Unvarnished, unem-bellished.n. An extent of level, or nearly level, land; a region not noticeably diversified with mountains, hills, or valleys.n. A field; especially, a field of battle.n. An open space surrounded by houses: as, St. Mary's Plain; the Theater Plain, in Norwich.In a plain manner; plainly; clearly; openly; frankly; bluntly.To make plain, level, or even; smooth; clear.To make plain or clear; explain.To lament; wail; mourn.To whinny: said of a horse.To lament; bewail; bemoan; mourn over.In old music, said of certain graces or embellishments, like the beat, backfall, etc., when without extension by a shake: opposed to shaked. Also called smooth.