Plain \Plain\, a. [Compar. Plainer; superl. Plainest.] [F.,
   level, flat, fr. L. planus, perhaps akin to E. floor. Cf.
   Llano, Piano, Plan, Plane level, a level surface.]
   1. Without elevations or depressions; flat; level; smooth;
      even. See Plane.
      [1913 Webster]

            The crooked shall be made straight, and the rough
            places plain.                         --Isa. xl. 4.
      [1913 Webster]

   2. Open; clear; unencumbered; equal; fair.
      [1913 Webster]

            Our troops beat an army in plain fight. --Felton.
      [1913 Webster]

   3. Not intricate or difficult; evident; manifest; obvious;
      clear; unmistakable. "'T is a plain case." --Shak.
      [1913 Webster]

   4.
      (a) Void of extraneous beauty or ornament; without
          conspicious embellishment; not rich; simple.
      (b) Not highly cultivated; unsophisticated; free from show
          or pretension; simple; natural; homely; common. "Plain
          yet pious Christians." --Hammond. "The plain people."
          --A. Lincoln.
      (c) Free from affectation or disguise; candid; sincere;
          artless; honest; frank. "An honest mind, and plain."
          --Shak.
      (d) Not luxurious; not highly seasoned; simple; as, plain
          food.
      (e) Without beauty; not handsome; homely; as, a plain
          woman.
      (f) Not variegated, dyed, or figured; as, plain muslin.
      (g) Not much varied by modulations; as, a plain tune.
          [1913 Webster]

   Plain battle, open battle; pitched battle. [Obs.]
      --Chaucer.

   Plain chant (Mus.) Same as Plain song, below.

   Plain chart (Naut.), a chart laid down on Mercator's
      projection.

   Plain dealer.
      (a) One who practices plain dealing.
      (b) A simpleton. [Obs.] --Shak.

   Plain dealing. See under Dealing.

   Plain molding (Join.), molding of which the surfaces are
      plain figures.

   Plain sewing, sewing of seams by simple and common
      stitches, in distinct from fancy work, embroidery, etc.;
      -- distinguished also from designing and fitting garments.
      

   Plain song.
      (a) The Gregorian chant, or canto fermo; the prescribed
          melody of the Roman Catholic service, sung in unison,
          in tones of equal length, and rarely extending beyond
          the compass of an octave.
      (b) A simple melody.

   Plain speaking, plainness or bluntness of speech.
      [1913 Webster]

   Syn: Level; flat; smooth; open; artless; unaffected;
        undisguised; frank; sincere; honest; candid; ingenuous;
        unembellished; downright; blunt; clear; simple;
        distinct; manifest; obvious; apparent. See Manifest.
        [1913 Webster]