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

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


Origin of jam

1700–10; apparently imitative; cf. champ1, dam1




a preserve of whole fruit, slightly crushed, boiled with sugar: strawberry jam.

Origin of jam

First recorded in 1720–30; perhaps special use of jam1
Related formsjam·like, jam·my, adjective


Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for jam

Contemporary Examples of jam

Historical Examples of jam

  • Treacle, you hear: and for that matter, Martha has no jam to give!

    Night and Morning, Complete

    Edward Bulwer-Lytton

  • You may make a charlotte with any sort of jam, marmalade, or fruit jelly.

  • Before he could recover, the second or tail section of the jam started to pull.

    The Forest

    Stewart Edward White

  • But they ate so much of the bread and butter and jam and cream that they could not eat the cake.

    Changing Winds

    St. John G. Ervine

  • Spread one half of them with jam, and lay the others on the top.

    The Skilful Cook

    Mary Harrison

British Dictionary definitions for jam



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)


abbreviation for

Bible James
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 jam

"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

jam 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 jam


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.