verb (used with object), jammed, jam·ming.

verb (used without object), jammed, jam·ming.


Origin of jam

1700–10; apparently imitative; cf. champ1, dam1
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for jamming

Contemporary Examples of jamming

Historical Examples of jamming

  • But the very closeness of the jamming saved us from these dangers.

    Dwellers in the Hills

    Melville Davisson Post

  • He wrenched at the door again, jamming down his helmet with one hand.

    The Aliens

    Murray Leinster

  • The crowd began caving at the edge and jamming at the centre.

    Eben Holden

    Irving Bacheller

  • How will that help him; jamming that iron-bound bucket on top of his head?

  • You're jamming the leaves all into a little mess and showing the stems!

    Reels and Spindles

    Evelyn Raymond

British Dictionary definitions for jamming



mountaineering a rock-climbing technique in which holds are got by wedging the hands and feet in suitable cracks



verb jams, jamming or jammed

(tr) to cram or wedge into or against somethingto jam paper into an incinerator
(tr) to crowd or packcars jammed the roads
to make or become stuck or lockedthe switch has jammed
(tr often foll by on) to activate suddenly (esp in the phrase jam on the brakes)
(tr) to block; congestto jam the drain with rubbish
(tr) to crush, bruise, or squeeze; smash
radio to prevent the clear reception of (radio communications or radar signals) by transmitting other signals on the same frequency
(intr) slang to play in a jam session


a crowd or congestion in a confined spacea traffic jam
the act of jamming or the state of being jammed
informal a difficult situation; predicamentto help a friend out of a jam
Derived Formsjammer, noun

Word Origin for jam

C18: probably of imitative origin; compare champ 1




a preserve containing fruit, which has been boiled with sugar until the mixture sets
slang something desirableyou want jam on it
jam today the principle of living for the moment

Word Origin for jam

C18: perhaps from jam 1 (the act of squeezing)
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for jamming



"to press tightly," also "to become wedged," 1706, of unknown origin, perhaps a variant of champ (v.). Of a malfunction in the moving parts of machinery, by 1851. Sense of "cause interference in radio signals" is from 1914. Related: Jammed; jamming. The adverb is recorded from 1825, from the verb.



"fruit preserve," 1730s, probably a special use of jam (v.) with a sense of "crush fruit into a preserve."



"a tight pressing between two surfaces," 1806, from jam (v.). Jazz meaning "short, free improvised passage performed by the whole band" dates from 1929, and yielded jam session (1933); but this is perhaps from jam (n.1) in sense of "something sweet, something excellent." Sense of "machine blockage" is from 1890, which probably led to the colloquial meaning "predicament, tight spot," first recorded 1914.

Online Etymology Dictionary, © 2010 Douglas Harper

jamming in Medicine




To block, congest, or clog.
To crush or bruise.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Idioms and Phrases with jamming


see under get in a bind.

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.