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.
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            [They] disdain the trammels of any sordid contract.
                                                  --Jeffrey.
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   5. An iron hook of various forms and sizes, used for handing
      kettles and other vessels over the fire.
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   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]