The Collaborative International Dictionary of English v.0.48:

Trap \Trap\, v. t. [imp. & p. p. Trapped; p. pr. & vb. n.
   Trapping.] [Akin to OE. trappe trappings, and perhaps from
   an Old French word of the same origin as E. drab a kind of
   cloth.]
   To dress with ornaments; to adorn; -- said especially of
   horses.
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         Steeds . . . that trapped were in steel all glittering.
                                                  --Chaucer.
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         To deck his hearse, and trap his tomb-black steed.
                                                  --Spenser.
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         There she found her palfrey trapped
         In purple blazoned with armorial gold.   --Tennyson.
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The Collaborative International Dictionary of English v.0.48:

Trap \Trap\, n. [Sw. trapp; akin to trappa stairs, Dan. trappe,
   G. treppe, D. trap; -- so called because the rocks of this
   class often occur in large, tabular masses, rising above one
   another, like steps. See Tramp.] (Geol.)
   An old term rather loosely used to designate various
   dark-colored, heavy igneous rocks, including especially the
   feldspathic-augitic rocks, basalt, dolerite, amygdaloid,
   etc., but including also some kinds of diorite. Called also
   trap rock.
   [1913 Webster]

   Trap tufa, Trap tuff, a kind of fragmental rock made up
      of fragments and earthy materials from trap rocks.
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The Collaborative International Dictionary of English v.0.48:

Trap \Trap\, a.
   Of or pertaining to trap rock; as, a trap dike.
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The Collaborative International Dictionary of English v.0.48:

Trap \Trap\, n. [OE. trappe, AS. treppe; akin to OD. trappe,
   OHG. trapo; probably fr. the root of E. tramp, as that which
   is trod upon: cf. F. trappe, which is trod upon: cf. F.
   trappe, which perhaps influenced the English word.]
   1. A machine or contrivance that shuts suddenly, as with a
      spring, used for taking game or other animals; as, a trap
      for foxes.
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            She would weep if that she saw a mouse
            Caught in a trap.                     --Chaucer.
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   2. Fig.: A snare; an ambush; a stratagem; any device by which
      one may be caught unawares.
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            Let their table be made a snare and a trap. --Rom.
                                                  xi. 9.
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            God and your majesty
            Protect mine innocence, or I fall into
            The trap is laid for me!              --Shak.
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   3. A wooden instrument shaped somewhat like a shoe, used in
      the game of trapball. It consists of a pivoted arm on one
      end of which is placed the ball to be thrown into the air
      by striking the other end. Also, a machine for throwing
      into the air glass balls, clay pigeons, etc., to be shot
      at.
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   4. The game of trapball.
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   5. A bend, sag, or partitioned chamber, in a drain, soil
      pipe, sewer, etc., arranged so that the liquid contents
      form a seal which prevents passage of air or gas, but
      permits the flow of liquids.
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   6. A place in a water pipe, pump, etc., where air accumulates
      for want of an outlet.
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   7. A wagon, or other vehicle. [Colloq.] --Thackeray.
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   8. A kind of movable stepladder. --Knight.
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   Trap stairs, a staircase leading to a trapdoor.

   Trap tree (Bot.) the jack; -- so called because it
      furnishes a kind of birdlime. See 1st Jack.
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The Collaborative International Dictionary of English v.0.48:

Trap \Trap\, v. t. [AS. treppan. See Trap a snare.]
   [1913 Webster]
   1. To catch in a trap or traps; as, to trap foxes.
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   2. Fig.: To insnare; to take by stratagem; to entrap. "I
      trapped the foe." --Dryden.
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   3. To provide with a trap; as, to trap a drain; to trap a
      sewer pipe. See 4th Trap, 5.
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The Collaborative International Dictionary of English v.0.48:

Trap \Trap\, v. i.
   To set traps for game; to make a business of trapping game;
   as, to trap for beaver.
   [1913 Webster]

WordNet (r) 3.0 (2006):

trap
    n 1: a device in which something (usually an animal) can be
         caught and penned
    2: drain consisting of a U-shaped section of drainpipe that
       holds liquid and so prevents a return flow of sewer gas
    3: something (often something deceptively attractive) that
       catches you unawares; "the exam was full of trap questions";
       "it was all a snare and delusion" [syn: trap, snare]
    4: a device to hurl clay pigeons into the air for trapshooters
    5: the act of concealing yourself and lying in wait to attack by
       surprise [syn: ambush, ambuscade, lying in wait,
       trap]
    6: informal terms for the mouth [syn: trap, cakehole,
       hole, maw, yap, gob]
    7: a light two-wheeled carriage
    8: a hazard on a golf course [syn: bunker, sand trap,
       trap]
    v 1: place in a confining or embarrassing position; "He was
         trapped in a difficult situation" [syn: trap, pin down]
    2: catch in or as if in a trap; "The men trap foxes" [syn:
       trap, entrap, snare, ensnare, trammel]
    3: hold or catch as if in a trap; "The gaps between the teeth
       trap food particles"
    4: to hold fast or prevent from moving; "The child was pinned
       under the fallen tree" [syn: trap, pin, immobilize,
       immobilise]

Moby Thesaurus II by Grady Ward, 1.0:

169 Moby Thesaurus words for "trap":
   Dionaea, French door, John Law, allure, allurement, ambuscade,
   ambush, ambushment, archway, artifice, back door, bag, bait,
   bait the hook, baited trap, barway, bazoo, beguile, birdlime,
   blind, bobby, booby trap, bulkhead, bull, carriage entrance, catch,
   catch out, catch up, cellar door, cellarway, chaps, charm, chops,
   come-on, confine, conspiracy, constable, deadfall, deathtrap,
   deceive, deception, decoy, decoy duck, device, door, doorjamb,
   doorpost, doorway, drawcard, drawing card, dupe, embouchure,
   endearment, enmesh, ensnare, ensnarl, entangle, enticement, entoil,
   entrap, enweb, face, feint, firetrap, flytrap, fool, foul,
   front door, gab, gambit, gate, gatepost, gateway, gendarme, gin,
   gob, ground bait, harpoon, hatch, hatchway, hold, hook, hook in,
   imprison, intrigue, inveigle, inveiglement, jaw, jaws, jowls, keep,
   kisser, land, lasso, lime, lintel, lips, lock, lure, lurking hole,
   machination, mandibles, maneuver, maw, maxilla, mesh, mine,
   mole trap, mousetrap, mouth, mug, mush, muzzle, nail, net, noose,
   oral cavity, paddy, peeler, pitfall, plot, ploy, police, porch,
   portal, porte cochere, postern, premaxilla, propylaeum, pylon,
   rattrap, rope, row, ruse, sack, scuttle, seducement, set gun,
   shadowing, side door, snag, snare, snarl, sniggle, spear,
   spread the toils, spring gun, springe, stalking-horse, stile,
   storm door, stratagem, subterfuge, surveillance, take, tangle,
   tangle up with, temptation, threshold, tollgate, trap door,
   trapfall, trick, trip, turnpike, turnstile, wile, wind, yap



V.E.R.A. -- Virtual Entity of Relevant Acronyms (February 2016):

TRAP
       Tandem Recursive Algorithm Process


The Jargon File (version 4.4.7, 29 Dec 2003):

trap


    1. n. A program interrupt, usually an interrupt caused by some exceptional
    situation in the user program. In most cases, the OS performs some action,
    then returns control to the program.

    2. vi. To cause a trap. ?These instructions trap to the monitor.? Also used
    transitively to indicate the cause of the trap. ?The monitor traps all
    input/output instructions.?

    This term is associated with assembler programming (interrupt or exception
    is more common among HLL programmers) and appears to be fading into
    history among programmers as the role of assembler continues to shrink.
    However, it is still important to computer architects and systems hackers
    (see system, sense 1), who use it to distinguish deterministically
    repeatable exceptions from timing-dependent ones (such as I/O interrupts).


The Free On-line Dictionary of Computing (30 December 2018):

trap

   1. A program interrupt, usually an interrupt caused by some
   exceptional situation in the user program.  In most cases, the
   OS performs some action, then returns control to the program.

   2. To cause a trap.  "These instructions trap to the monitor."
   Also used transitively to indicate the cause of the trap.
   "The monitor traps all input/output instructions."

   This term is associated with assembler programming
   ("interrupt" or "exception" is more common among HLL
   programmers) and appears to be fading into history among
   programmers as the role of assembler continues to shrink.
   However, it is still important to computer architects and
   systems hackers (see system, sense 1), who use it to
   distinguish deterministically repeatable exceptions from
   timing-dependent ones (such as I/O interrupts).

   [Jargon File]