The Collaborative International Dictionary of English v.0.48:

Jamb \Jamb\, Jambe \Jambe\, Jambeau \Jambeau\, n.
   See Jambes.
   [PJC]

The Collaborative International Dictionary of English v.0.48:

Jamb \Jamb\, n. [Prov. E. jaumb, jaum, F. jambe a leg, jambe de
   force a principal rafter. See Gambol.]
   [1913 Webster]
   1. (Arch) The vertical side of any opening, as a door or
      fireplace; hence, less properly, any narrow vertical
      surface of wall, as the of a chimney-breast or of a pier,
      as distinguished from its face. --Gwilt.
      [1913 Webster]

   2. (Mining) Any thick mass of rock which prevents miners from
      following the lode or vein.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Jamb \Jamb\, v. t.
   See Jam, v. t. & i.
   [1913 Webster] Jambe
   Jamb

WordNet (r) 3.0 (2006):

jamb
    n 1: upright consisting of a vertical side member of a door or
         window frame

Moby Thesaurus II by Grady Ward, 1.0:

43 Moby Thesaurus words for "jamb":
   Samson post, ankle, baluster, balustrade, banister, bayonet legs,
   bowlegs, calf, cnemis, doorjamb, doorpost, drumstick, foreleg,
   gamb, gambrel, gatepost, gigot, ham, hind leg, hitching post, hock,
   king post, knee, leg, limb, milepost, mullion, podite,
   popliteal space, post, scissor-legs, shank, shin, signpost,
   snubbing post, stanchion, standard, stems, stile, stumps, tarsus,
   trotters, upright