|—vb (often foll by on) , jams, jamming, jammed|
|1.||(tr) to cram or wedge into or against something: to jam paper into an incinerator|
|2.||(tr) to crowd or pack: cars jammed the roads|
|3.||to make or become stuck or locked: the switch has jammed|
|4.||to activate suddenly (esp in the phrase jam on the brakes)|
|5.||(tr) to block; congest: to jam the drain with rubbish|
|6.||(tr) to crush, bruise, or squeeze; smash|
|7.||radio to prevent the clear reception of (radio communications or radar signals) by transmitting other signals on the same frequency|
|8.||slang (intr) to play in a jam session|
|9.||a crowd or congestion in a confined space: a traffic jam|
|10.||the act of jamming or the state of being jammed|
|11.||informal a difficult situation; predicament: to help a friend out of a jam|
|12.||See jam session|
|[C18: probably of imitative origin; compare |
v. jammed, jam·ming, jams
To block, congest, or clog.
To crush or bruise.
in electronics, broadcasting a strong signal that overrides or obscures a target signal. Jamming of radio and television stations broadcasting from beyond borders may be carried out by a country that does not wish its citizens to receive programs from abroad. In military activities, jamming is frequently employed to confuse enemy radar or communications. The techniques of jamming are many and varied, but most of them simply consist of broadcasting a powerful radio signal, modulated with noise, on the precise frequency of the signal being jammed.
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