Nouns

(n)jampreserve of crushed fruit
(n)fix, hole, jam, mess, muddle, pickle, kettle of fishinformal terms for a difficult situation“he got into a terrible fix”, “he made a muddle of his marriage”
(n)crush, jam, pressa dense crowd of people
(n)jamming, electronic jamming, jamdeliberate radiation or reflection of electromagnetic energy for the purpose of disrupting enemy use of electronic devices or systems

Verbs

(v)throng, mob, pack, pile, jampress tightly together or cram“The crowd packed the auditorium”
(v)jampush down forcibly“The driver jammed the brake pedal to the floor”
(v)jam, crushcrush or bruise“jam a toe”
(v)jam, blockinterfere with or prevent the reception of signals“Jam the Voice of America”, “block the signals emitted by this station”
(v)jamget stuck and immobilized“the mechanism jammed”
(v)jam, jampack, ram, chock up, cram, wadcrowd or pack to capacity“the theater was jampacked”
(v)obstruct, obturate, impede, occlude, jam, block, close upblock passage through“obstruct the path”