[1] : The Collaborative International Dictionary of English v.0.48

jam \jam\, v. t. imp.  p. p. jammed ja^md; p. pr.  vb.
   n. jamming. either fr. jamb, as if squeezed between
   jambs, or more likely from the same source as champ see
   champ.
   1913 webster
   1. to press into a close or tight position; to crowd; to
      squeeze; to wedge in; to cram; as, rock fans jammed the
      theater for the concert.
      1913 webster

            the ship . . . jammed in between two rocks. --de
                                                  foe.
      1913 webster

   2. to crush or bruise; as, to jam a finger in the crack of a
      door. colloq.
      1913 webster

   3. naut. to bring a vessel so close to the wind that half
      her upper sails are laid aback. --w. c. russell.
      1913 webster

   4. to block or obstruct by packing too much people or
      objects into; as, shoppers jammed the aisles during the
      fire sale.
      pjc

   5. radio to interfere with a radio signal by sending
      other signals of the same or nearby frequency; as, the
      soviets jammed radio free europe broadcasts for years
      during the cold war.
      pjc

   6. to cause to become nonfunctional by putting something in
      that blocks the movement of a part or parts; as, he jammed
      the drawer by putting in too many loose papers; he jammed
      the lock by trying to pick it.
      pjc
see also:
jammed jamming champ 

[2] : WordNet (r) 2.0

jamming
     see jam
see also:
jam 

[3] : WordNet (r) 2.0

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
see also:
fix hole mess muddle pickle kettle of fish 
crush press jamming electronic jamming throng 
mob pack pile block jampack 
ram chock up cram wad obstruct 
obturate impede occlude close up free 
jammed 

[4] : WordNet (r) 2.0

jamming
     n : deliberate radiation or reflection of electromagnetic energy
         for the purpose of disrupting enemy use of electronic
         devices or systems syn: electronic jamming, jam
see also:
electronic jamming jam 

Jamming >> J Words
Jamming, definition of term: Jamming
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