Dictionary definition · jam
noun
- preserve of crushed fruit
- informal terms for a difficult situation"he got into a terrible fix"
- a dense crowd of people
- deliberate radiation or reflection of electromagnetic energy for the purpose of disrupting enemy use of electronic devices or systems
verb
- press tightly together or cram"The crowd packed the auditorium"
- push down forcibly"The driver jammed the brake pedal to the floor"
- crush or bruise"jam a toe"
- interfere with or prevent the reception of signals"Jam the Voice of America"
- get stuck and immobilized"the mechanism jammed"
- crowd or pack to capacity"the theater was jampacked"
- block passage through"obstruct the path"
Source: Open English WordNet (CC BY 4.0).