1. [n]  a basic knitting stitch
2. [n]  extensive tract of level open land; "they emerged from the woods onto a vast open plain"; "he longed for the fields of his youth"
3. [adv]  unmistakably; "the answer is obviously wrong"; "she was in bed and evidently in great pain"; "he was manifestly too important to leave off the guest list"; "it is all patently nonsense"; "she has apparently been living here for some time"; "I thought he owned the property, but apparently not"; "You are plainly wrong"; (`plain' is often used informally for `plainly' as in"he is plain stubborn")
4. [adj]  lacking embellishment or ornamentation; "a plain hair style"; "unembellished white walls"; "functional architecture featuring stark unornamented concrete"
5. [adj]  lacking in physical beauty or proportion; "a homely child"; "several of the buildings were downright homely"; "a plain girl with a freckled face"
6. [adj]  free from any effort to soften to disguise; "the plain and unvarnished truth"; "the unvarnished candor of old people and children"
7. [adj]  comprehensible to the general public; "written for the popular press in plain nontechnical language"
8. [adj]  clearly apparent or obvious to the mind or senses; "the effects of the drought are apparent to anyone who sees the parched fields"; "evident hostility"; "manifest disapproval"; "patent advantages"; "made his meaning plain"; "it is plain that he is no reactionary"; "in plain view"
9. [adj]  lacking patterns especially in color
10. [adj]  not elaborate or elaborated; simple; "plain food"; "stuck to the plain facts"; "a plain blue suit"; "a plain rectangular brick building"
11. [adj]  not mixed with extraneous elements; "plain water"; "sheer wine"; "not an unmixed blessing"
12. [adj]  lacking stylistic embellishment; "a literal description"; "wrote good but plain prose"; "a plain unadorned account of the coronation"; "a forthright unembellished style"
13. [v]  express complaints, discontent, displeasure, or unhappiness; "My mother complains all day"; "She has a lot to kick about"

1. \Plain\, v. i. [OE. playne, pleyne, fr. F. plaindre. See
   {Plaint}.]
   To lament; to bewail; to complain. [Archaic & Poetic]
   --Milton.
         We with piteous heart unto you pleyne.   --Chaucer.
   

2. \Plain\, v. t.
   To lament; to mourn over; as, to plain a loss. [Archaic &
   Poetic] --Sir J. Harrington.
   

3. \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}.
            The crooked shall be made straight, and the rough
            places plain.                         --Isa. xl. 4.
   2. Open; clear; unencumbered; equal; fair.
            Our troops beat an army in plain fight. --Felton.
   3. Not intricate or difficult; evident; manifest; obvious;
      clear; unmistakable. ``'T is a plain case.'' --Shak.
   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.
   {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.
   Syn: Level; flat; smooth; open; artless; unaffected;
        undisguised; frank; sincere; honest; candid; ingenuous;
        unembellished; downright; blunt; clear; simple;
        distinct; manifest; obvious; apparent. See {Manifest}.
   

4. \Plain\, adv.
   In a plain manner; plainly. ``To speak short and pleyn.''
   --Chaucer. ``To tell you plain.'' --Shak.
   

5. \Plain\, 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.
            Descending fro the mountain into playn. --Chaucer.
            Him the Ammonite Worshiped in Rabba and her watery
            plain.                                --Milton.
   2. A field of battle. [Obs.] --Arbuthnot.
            Lead forth my soldiers to the plain.  --Shak.
   

6. \Plain\, 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.]
            We would rake Europe rather, plain the East.
                                                  --Wither.
   2. To make plain or manifest; to explain.
            What's dumb in show, I'll plain in speech. --Shak.
   

Programming LAnguage for INteraction. Pascal-like, with extensions for database, string handling, exceptions and pattern matching. "Revised Report on the Programming Language PLAIN", A. Wasserman, SIGPLAN Notices 6(5):59-80 (May 1981).

(1.) Heb. 'abel (Judg. 11:33), a "grassy plain" or "meadow." Instead of "plains of the vineyards," as in the Authorized Version, the Revised Version has "Abel-cheramim" (q.v.), comp. Judg. 11:22; 2 Chr. 16:4.

(2.) Heb. 'elon (Gen. 12:6; 13:18; 14:13; 18:1; Deut. 11:30; Judg. 9:6), more correctly "oak," as in the Revised Version; margin, "terebinth."

(3.) Heb. bik'ah (Gen. 11:2; Neh. 6:2; Ezek. 3:23; Dan. 3:1), properly a valley, as rendered in Isa. 40:4, a broad plain between mountains. In Amos 1:5 the margin of Authorized Version has "Bikathaven."

(4.) Heb. kikar, "the circle," used only of the Ghor, or the low ground along the Jordan (Gen. 13:10-12; 19:17, 25, 28, 29; Deut. 34:3; 2 Sam. 18:23; 1 Kings 7:46; 2 Chr. 4:17; Neh. 3:22; 12:28), the floor of the valley through which it flows. This name is applied to the Jordan valley as far north as Succoth.

(5.) Heb. mishor, "level ground," smooth, grassy table-land (Deut. 3:10; 4:43; Josh. 13:9, 16, 17, 21; 20:8; Jer. 48:21), an expanse of rolling downs without rock or stone. In these passages, with the article prefixed, it denotes the plain in the tribe of Reuben. In 2 Chr. 26:10 the plain of Judah is meant. Jerusalem is called "the rock of the plain" in Jer. 21:13, because the hills on which it is built rise high above the plain.

(6.) Heb. 'arabah, the valley from the Sea of Galilee southward to the Dead Sea (the "sea of the plain," 2 Kings 14:25; Deut. 1:1; 2:8), a distance of about 70 miles. It is called by the modern Arabs the Ghor. This Hebrew name is found in Authorized Version (Josh. 18:18), and is uniformly used in the Revised Version. Down through the centre of this plain is a ravine, from 200 to 300 yards wide, and from 50 to 100 feet deep, through which the Jordan flows in a winding course. This ravine is called the "lower plain."

The name Arabah is also applied to the whole Jordan valley from Mount Hermon to the eastern branch of the Red Sea, a distance of about 200 miles, as well as to that portion of the valley which stretches from the Sea of Galilee to the same branch of the Red Sea, i.e., to the Gulf of Akabah about 100 miles in all.

(7.) Heb. shephelah, "low ground," "low hill-land," rendered "vale" or "valley" in Authorized Version (Josh. 9:1; 10:40; 11:2; 12:8; Judg. 1:9; 1 Kings 10:27). In Authorized Version (1 Chr. 27:28; 2 Chr. 26:10) it is also rendered "low country." In Jer. 17:26, Obad. 1:19, Zech. 7:7, "plain." The Revised Version renders it uniformly "low land." When it is preceded by the article, as in Deut. 1:7, Josh. 11:16; 15:33, Jer. 32:44; 33:13, Zech. 7:7, "the shephelah," it denotes the plain along the Mediterranean from Joppa to Gaza, "the plain of the Philistines." (See VALLEY.)