The Collaborative International Dictionary of English v.0.48:

Butt \Butt\, But \But\, n. [F. but butt, aim (cf. butte knoll),
   or bout, OF. bot, end, extremity, fr. boter, buter, to push,
   butt, strike, F. bouter; of German origin; cf. OHG. b[=o]zan,
   akin to E. beat. See Beat, v. t.]
   1. A limit; a bound; a goal; the extreme bound; the end.
      [1913 Webster]

            Here is my journey's end, here my butt
            And very sea mark of my utmost sail.  --Shak.
      [1913 Webster]

   Note: As applied to land, the word is nearly synonymous with
         mete, and signifies properly the end line or boundary;
         the abuttal.
         [1913 Webster]

   2. The larger or thicker end of anything; the blunt end, in
      distinction from the sharp end; as, the butt of a rifle.
      Formerly also spelled but. See 2nd but, n. sense 2.
      [1913 Webster +PJC]

   3. A mark to be shot at; a target. --Sir W. Scott.
      [1913 Webster]

            The groom his fellow groom at butts defies,
            And bends his bow, and levels with his eyes.
                                                  --Dryden.
      [1913 Webster]

   4. A person at whom ridicule, jest, or contempt is directed;
      as, the butt of the company.
      [1913 Webster]

            I played a sentence or two at my butt, which I
            thought very smart.                   --Addison.
      [1913 Webster]

   5. A push, thrust, or sudden blow, given by the head of an
      animal; as, the butt of a ram.
      [1913 Webster]

   6. A thrust in fencing.
      [1913 Webster]

            To prove who gave the fairer butt,
            John shows the chalk on Robert's coat. --Prior.
      [1913 Webster]

   7. A piece of land left unplowed at the end of a field.
      [1913 Webster]

            The hay was growing upon headlands and butts in
            cornfields.                           --Burrill.
      [1913 Webster]

   8. (Mech.)
      (a) A joint where the ends of two objects come squarely
          together without scarfing or chamfering; -- also
          called butt joint.
      (b) The end of a connecting rod or other like piece, to
          which the boxing is attached by the strap, cotter, and
          gib.
      (c) The portion of a half-coupling fastened to the end of
          a hose.
          [1913 Webster]

   9. (Shipbuilding) The joint where two planks in a strake
      meet.
      [1913 Webster]

   10. (Carp.) A kind of hinge used in hanging doors, etc.; --
       so named because fastened on the edge of the door, which
       butts against the casing, instead of on its face, like
       the strap hinge; also called butt hinge.
       [1913 Webster]

   11. (Leather Trade) The thickest and stoutest part of tanned
       oxhides, used for soles of boots, harness, trunks.
       [1913 Webster]

   12. The hut or shelter of the person who attends to the
       targets in rifle practice.
       [1913 Webster]

   13. The buttocks; as, get up off your butt and get to work;
       -- used as a euphemism, less objectionable than ass.
       [slang]

   Syn: ass, rear end, derriere, behind, rump, heinie.
        [PJC]

   Butt chain (Saddlery), a short chain attached to the end of
      a tug.

   Butt end. The thicker end of anything. See But end, under
      2d But.
      [1913 Webster]

            Amen; and make me die a good old man!
            That's the butt end of a mother's blessing. --Shak.
      [1913 Webster]

   A butt's length, the ordinary distance from the place of
      shooting to the butt, or mark.

   Butts and bounds (Conveyancing), abuttals and boundaries.
      In lands of the ordinary rectangular shape, butts are the
      lines at the ends (F. bouts), and bounds are those on the
      sides, or sidings, as they were formerly termed.
      --Burrill.

   Bead and butt. See under Bead.

   Butt and butt, joining end to end without overlapping, as
      planks.

   Butt weld (Mech.), a butt joint, made by welding together
      the flat ends, or edges, of a piece of iron or steel, or
      of separate pieces, without having them overlap. See
      Weld.

   Full butt, headfirst with full force. [Colloq.] "The
      corporal . . . ran full butt at the lieutenant."
      --Marryat.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Butt \Butt\, v. t.
   To strike by thrusting the head against; to strike with the
   head.
   [1913 Webster]

         Two harmless lambs are butting one the other. --Sir H.
                                                  Wotton.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Butt \Butt\, v. i. [imp. & p. p. Butted; p. pr. & vb. n.
   Butting.] [OE. butten, OF. boter to push, F. bouter. See
   Butt an end, and cf. Boutade.]
   1. To join at the butt, end, or outward extremity; to
      terminate; to be bounded; to abut. [Written also but.]
      [1913 Webster]

            And Barnsdale there doth butt on Don's well-watered
            ground.                               --Drayton.
      [1913 Webster]

   2. To thrust the head forward; to strike by thrusting the
      head forward, as an ox or a ram. [See Butt, n.]
      [1913 Webster]

            A snow-white steer before thine altar led,
            Butts with his threatening brows.     --Dryden.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Butt \Butt\, n. [F. botte, boute, LL. butta. Cf. Bottle a
   hollow vessel.]
   A large cask or vessel for wine or beer. It contains two
   hogsheads.
   [1913 Webster]

   Note: A wine butt contains 126 wine gallons (= 105 imperial
         gallons, nearly); a beer butt 108 ale gallons (= about
         110 imperial gallons).
         [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Butt \Butt\, n. (Zool.)
   The common English flounder.
   [1913 Webster]

WordNet (r) 3.0 (2006):

butt
    n 1: thick end of the handle [syn: butt, butt end]
    2: the part of a plant from which the roots spring or the part
       of a stalk or trunk nearest the roots
    3: a victim of ridicule or pranks [syn: butt, goat,
       laughingstock, stooge]
    4: the fleshy part of the human body that you sit on; "he
       deserves a good kick in the butt"; "are you going to sit on
       your fanny and do nothing?" [syn: buttocks, nates,
       arse, butt, backside, bum, buns, can,
       fundament, hindquarters, hind end, keister,
       posterior, prat, rear, rear end, rump, stern,
       seat, tail, tail end, tooshie, tush, bottom,
       behind, derriere, fanny, ass]
    5: sports equipment consisting of an object set up for a
       marksman or archer to aim at [syn: target, butt]
    6: finely ground tobacco wrapped in paper; for smoking [syn:
       cigarette, cigaret, coffin nail, butt, fag]
    7: a joint made by fastening ends together without overlapping
       [syn: butt joint, butt]
    8: a large cask (especially one holding a volume equivalent to 2
       hogsheads or 126 gallons)
    9: the small unused part of something (especially the end of a
       cigarette that is left after smoking) [syn: butt, stub]
    v 1: lie adjacent to another or share a boundary; "Canada
         adjoins the U.S."; "England marches with Scotland" [syn:
         border, adjoin, edge, abut, march, butt, butt
         against, butt on]
    2: to strike, thrust or shove against; "He butted his sister out
       of the way"; "The goat butted the hiker with his horns" [syn:
       butt, bunt]
    3: place end to end without overlapping; "The frames must be
       butted at the joints"

Moby Thesaurus II by Grady Ward, 1.0:

367 Moby Thesaurus words for "butt":
   Thule, Ultima Thule, abut, abut on, adjoin, advance, afterglow,
   afterimage, aim, ankle, articulate, articulation, assault,
   backside, bacon, balance, barrel, batten, batten down,
   be contiguous, be in contact, bear, bear upon, bearing, behind,
   bit, bitter end, bolt, boost, border, border on, bottom,
   bottom dollar, boundary, bowl, breech, buck, buckle, bull,
   bulldoze, bump, bump against, bunt, butt against, butt end,
   buttocks, button, by-end, by-purpose, byword, byword of reproach,
   candle ends, carton of cigarettes, cervix, chaff, chip,
   chitterlings, chump, chunk, cig, cigarette, cigarette butt,
   cigarette case, clasp, cleat, clinch, clip, clipping, closure,
   cochon de lait, collop, communicate, conjoin, connect,
   connecting link, connecting rod, connection, coupling, cracklings,
   cram, croup, crowd, crumb, crupper, cut, cutting, debris,
   deck of cigarettes, derision, derriere, destination, detritus, dig,
   dollop, dovetail, drive, driving force, dupe, elbow, embrace, end,
   end in view, extreme, extremity, fag, fag end, fair game, fall guy,
   fanny, farthest bound, fat back, figure of fun, filings,
   final cause, flitch, fool, force, forward, fossil, fragment, game,
   gammon, gazingstock, gliding joint, goad, goal, goat, gob, gobbet,
   gudgeon, gull, ham, ham steak, haslet, hasp, haunches, head,
   headcheese, hind end, hinge, hinged joint, hip, hitch, hogshead,
   holdover, hook, hunk, hurtle, husks, hustle, impel, impulsion,
   interface, interfere, interrupt, intrude, jab, jam, jambon,
   jambonneau, jest, jestingstock, jog, joggle, join, joining, joint,
   joke, jolt, jostle, jumping-off place, juncture, keg, kibitz, knee,
   knuckle, lard, latch, laughingstock, leavings, leftovers, lie by,
   limit, line, link, lock, lump, march, mark, meddle, meet, miter,
   mock, mockery, modicum, moiety, monkey, morsel, mortise,
   motive power, move, nail, nates, neck, neighbor, nib, nudge,
   object, object in mind, objective, odds and ends, offscourings,
   orts, paring, parings, particle, patsy, pedal, peg, picnic ham,
   piece, pieds de cochon, pig, pigeon, pile drive, pilgarlic, pin,
   pipe, pivot, pivot joint, point, poke, pole, pork, porkpie,
   posterior, prat, press, pressure, prey, prod, propel, propelling,
   propelment, propulsion, pulsion, punch, pursuit, push, pushing,
   quarry, quintain, rabbet, rags, ram, ram down, rasher, rattle,
   rear, rear end, reason for being, refuse, relics, remainder,
   remains, remnant, residue, residuum, rest, rivet, roach, roll, row,
   rubbish, ruins, rump, run, run against, salt pork, sawdust, scarf,
   scoop, scourings, scrap, scraps, screw, seam, sew, shadow, shake,
   shard, shaving, shavings, shiver, shoulder, shove, shoving, shred,
   shunt, side of bacon, sitting duck, skewer, slice, sliver,
   small ham, smithereen, smoke, snack, snap, snatch, snip, snipe,
   snippet, sowbelly, splinter, sport, stand by, staple, stick,
   stitch, stock, straw, stress, stub, stubble, stump, sucker,
   suckling pig, survival, suture, sweep, sweep along, sweepings,
   symphysis, tack, tag, tag end, tail, tail end, tamp, target,
   tatter, teleology, thrust, tie rod, tip, toggle, toggle joint,
   touch, toy, trace, treadle, troll, trotters, trundle, tun,
   ultimate aim, union, verge, verge upon, vestige, victim, waste,
   wedge, weld, wrist, zipper



Bouvier's Law Dictionary, Revised 6th Ed (1856):

BUTT. A measure of capacity, equal to one hundred and eight gallons. See
Measure.