jam
     n 1: preserve of crushed fruit
     2: informal terms for a difficult situation; "he got into a
        terrible fix"; "he made a muddle of his marriage" [syn: fix,
         hole, mess, muddle, pickle, kettle of fish]
     3: a dense crowd of people [syn: crush, press]
     4: deliberate radiation or reflection of electromagnetic energy
        for the purpose of disrupting enemy use of electronic
        devices or systems [syn: jamming, electronic jamming]
     v 1: press tightly together or cram; "The crowd packed the
          auditorium" [syn: throng, mob, pack, pile]
     2: push down forcibly; "The driver jammed the brake pedal to
        the floor"
     3: crush or bruise; "jam a toe" [syn: crush]
     4: interfere with or prevent the reception of signals; "Jam the
        Voice of America"; "block the signals emitted by this
        station" [syn: block]
     5: get stuck and immobilized; "the mechanism jammed"
     6: crowd or pack to capacity; "the theater was jampacked" [syn:
         jampack, ram, chock up, cram, wad]
     7: block passage through; "obstruct the path" [syn: obstruct,
         obturate, impede, occlude, block, close up]
        [ant: free]
     [also: jamming, jammed]

Jam \Jam\, n. (Mining)
   See Jamb.

Jam \Jam\, v. t. [imp. & p. p. Jammed; p. pr. & vb. n.
   Jamming.] [Either fr. jamb, as if squeezed between jambs,
   or more likely from the same source as champ See Champ.]
   1. To press into a close or tight position; to crowd; to
      squeeze; to wedge in.

            The . . . jammed in between two rocks. --De Foe.

   2. To crush or bruise; as, to jam a finger in the crack of a
      door. [Colloq.]

   3. (Naut.) To bring (a vessel) so close to the wind that half
      her upper sails are laid aback. --W. C. Russell.

Jam \Jam\, n.
   1. A mass of people or objects crowded together; also, the
      pressure from a crowd; a crush; as, a jam in a street; a
      jam of logs in a river.

   2. An injury caused by jamming. [Colloq.]

Jam \Jam\, n. [Per. or Hind. j[=a]mah garment, robe.]
   A kind of frock for children.

Jam \Jam\, n. [Prob. fr. jam, v.; but cf. also Ar. jamad ice,
   jelly, j[=a]mid congealed, jamd congelation, ice.]
   A preserve of fruit boiled with sugar and water; as,
   raspberry jam; currant jam; grape jam.

   Jam nut. See Check nut, under Check.

   Jam weld (Forging), a butt weld. See under Butt.

JaM

        John and Martin.  An interpreted FORTH-like graphics
        language by John Warnock and Martin Newell, Xerox PARC,
        1978.  JaM was the forerunner of both Interpress and
        PostScript.  It is mentioned in PostScript Language
        reference Manual, Adobe Systems, A-W 1985.

jam

        A condition on a network where two nodes transmitting
        simultaneously detect the collision and continue to transmit
        for a certain time (4 to 6 bytes on Ethernet) to ensure that
        the collision has been detected by all nodes involved.

        (1994-12-12)