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1. A number of vehicles blocking one another until they can scarcely move
   - traffic jam, snarl-up
    
2. A dense crowd of people
   - crush, press
    
3. Preserve of crushed fruit
    
4. [informal] The quality of being almost beyond one's ability to deal with and requiring a great effort to achieve a positive result
   - difficulty, difficultness, fix [informal], hole [informal], mess [informal], muddle [informal], pickle [informal], kettle of fish [informal]
    
5. Deliberate radiation or reflection of electromagnetic energy for the purpose of disrupting enemy use of electronic devices or systems
   - jamming, electronic jamming
    
6. A blockage or something stuck that prevents a device from working properly
   "there's a jam in the printer"
    
7. [informal] (popular music) an informal, impromptu performance or rehearsal

1. Press tightly together or cram
   "The crowd jammed the auditorium";
   - throng, mob, pack, pile
    
2. Push down forcibly
   "The driver jammed the brake pedal to the floor"
    
3. Hurt or bruise with a squashing force
   "jam a toe";
   - crush
    
4. Interfere with or prevent the reception of signals
   "Jam the Voice of America";
   - block
    
5. Get stuck and immobilized
   "the mechanism jammed"
    
6. Crowd or pack to capacity
   "the theatre was jammed";
   - jampack [informal], ram, cram, wad
    
7. Block passage through
   "jam the path";
   - obstruct, obturate, impede, occlude, block, close up
    
8. [informal] (popular music) play music in a group, esp. improvising

Sounds like: its, i, jam

Derived forms: jammed, jams, jamming

See also: difficult, hard

Type of: break up, bruise, conserve, conserves, contuse, crowd, crowd together, cut off, disrupt, ECM, electronic countermeasures, entrammel [literary], fetter [literary], force, hinder, impede, interrupt, malfunction, misfunction, preserve, preserves, push, quality, stuff, trammel [literary]

Encyclopedia: Jam, Khuzestan