v. t. [ imp. & p. p. Plained p. pr. & vb. n. Plaining. ] [ Cf. Plane, v. ] 1. To plane or level; to make plain or even on the surface. [ R. ] [ 1913 Webster ]

We would rake Europe rather, plain the East. Wither. [ 1913 Webster ]

2. To make plain or manifest; to explain. [ 1913 Webster ]

What's dumb in show, I'll plain in speech. Shak. [ 1913 Webster ]

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 ]

adv. In a plain manner; plainly. “To speak short and pleyn.” Chaucer. “To tell you plain.” Shak. [ 1913 Webster ]

v. i. [ OE. playne, pleyne, fr. F. plaindre. See Plaint. ] To lament; to bewail; to complain. [ Archaic & Poetic ] Milton. [ 1913 Webster ]

We with piteous heart unto you pleyne. Chaucer. [ 1913 Webster ]

n. [ Cf. OF. plaigne, F. plaine. See Plain, a. ] 1. Level land; usually, an open field or a broad stretch of land with an even surface, or a surface little varied by inequalities; as, the plain of Jordan; the American plains, or prairies. [ 1913 Webster ]

Descending fro the mountain into playn. Chaucer. [ 1913 Webster ]

Him the Ammonite
Worshiped in Rabba and her watery plain. Milton. [ 1913 Webster ]

2. A field of battle. [ Obs. ] Arbuthnot. [ 1913 Webster ]

Lead forth my soldiers to the plain. Shak. [ 1913 Webster ]

v. t. To lament; to mourn over; as, to plain a loss. [ Archaic & Poetic ] Sir J. Harrington. [ 1913 Webster ]

n. [ See 1st Plain. ] (Law) One who makes complaint; the plaintiff. [ Obs. ] [ 1913 Webster ]

a. Practicing plain dealing; artless. See Plain dealing, under Dealing. Shak. [ 1913 Webster ]

a. Frank; sincere; artless. Milton. -- Plain"-heart`ed*ness, n. [1913 Webster]

a. Complaining. [ Poetic ] Bryant. [ 1913 Webster ]