The Collaborative International Dictionary of English v.0.48:

Trammel \Tram"mel\, n. [F. tramail, tr['e]mail, a net, LL.
   tremaculum, tremacle, a kind of net for taking fish; L. tres
   three + macula a mesh. See Three, and Mail armor.]
   1. A kind of net for catching birds, fishes, or other prey.
      --Carew.
      [1913 Webster]

   2. A net for confining a woman's hair. --Spenser.
      [1913 Webster]

   3. A kind of shackle used for regulating the motions of a
      horse and making him amble.
      [1913 Webster]

   4. Fig.: Whatever impedes activity, progress, or freedom, as
      a net or shackle.
      [1913 Webster]

            [They] disdain the trammels of any sordid contract.
                                                  --Jeffrey.
      [1913 Webster]

   5. An iron hook of various forms and sizes, used for handing
      kettles and other vessels over the fire.
      [1913 Webster]

   6. (Mech.)
      (a) An instrument for drawing ellipses, one part of which
          consists of a cross with two grooves at right angles
          to each other, the other being a beam carrying two
          pins (which slide in those grooves), and also the
          describing pencil.
      (b) A beam compass. See under Beam.
          [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Trammel \Tram"mel\, v. t. [imp. & p. p. Trammeledor
   Trammelled; p. pr. & vb. n. Trammeling, or
   Trammelling.]
   1. To entangle, as in a net; to catch. [R.] --Shak.
      [1913 Webster]

   2. To confine; to hamper; to shackle.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Ellipsograph \El*lip"so*graph\, n. [Ellipse + graph: cf. F.
   ellipsographe.]
   An instrument for describing ellipses; -- called also
   trammel.
   [1913 Webster]

WordNet (r) 3.0 (2006):

trammel
    n 1: a fishing net with three layers; the outer two are coarse
         mesh and the loose inner layer is fine mesh [syn: trammel
         net, trammel]
    2: an adjustable pothook set in a fireplace
    3: a restraint that is used to teach a horse to amble
    4: a restraint that confines or restricts freedom (especially
       something used to tie down or restrain a prisoner) [syn:
       shackle, bond, hamper, trammel]
    v 1: catch in or as if in a trap; "The men trap foxes" [syn:
         trap, entrap, snare, ensnare, trammel]
    2: place limits on (extent or access); "restrict the use of this
       parking lot"; "limit the time you can spend with your
       friends" [syn: restrict, restrain, trammel, limit,
       bound, confine, throttle]

Moby Thesaurus II by Grady Ward, 1.0:

137 Moby Thesaurus words for "trammel":
   Oregon boat, anchor, arrest, bar, bearing rein, bilbo, bind, bit,
   block, bond, bonds, brake, bridle, burden, camisole, chain, chains,
   check, checkrein, checks, chock, circumscribe, clog, collar,
   confine, constipate, constrain, constraints, countercheck, cramp,
   cripple, cuffs, cumber, curb, curb bit, curbs, damper, deter,
   deterrents, doorstop, drag, drag sail, drift anchor, drift sail,
   drogue, embarrass, embrangle, enchain, encumber, enmesh, ensnarl,
   entangle, entoil, entrammel, entrap, entwine, fasten, fetter, gag,
   gyve, gyves, halter, hamper, hamstring, handcuff, handcuffs,
   handicap, handicaps, hinder, hindrances, hobble, hobbles, hog-tie,
   holdback, hopple, hopples, impede, involve, irons, lame, lash,
   leading strings, leash, lime, limit, lumber, make fast, manacle,
   martingale, moor, muzzle, net, obstacles, obstruct, peg down,
   pelham, picket, pillory, pin down, pinion, press down,
   put in irons, reins, remora, restrain, restraint, restraints, rope,
   saddle with, scotch, sea anchor, secure, shackle, shackles,
   snaffle, snags, snarl, spoke, stagnate, stay, stifle, stocks, stop,
   straightjacket, strait-waistcoat, straitjacket, stranglehold,
   strap, tangle, tether, tie, tie down, tie up, toil, trammels,
   weigh down, yoke