jam

JAM/ˈd͡ʒæm/

Pluraljams

Verbjams, jamming, jammed

27 meanings of jam

Practice

1
fruit spreadnouncountable or uncountable
A sweet spread made by boiling fruit with sugar until it sets, commonly used on bread or toast or in tarts.
The recipe calls for a thick layer of apricot jam between the cake layers.
Grandma boils plums every fall to make jam for the winter.
UsageNamed by fruit (strawberry jam) and measured in a jar of jam or a spoonful of jam.
Similarjelly, preserve, conserve
2
blockagenouncountable
A crush or blockage in which movement is slowed or stopped, as when traffic, a crowd or machinery gets stuck.
A jam in the conveyor belt brought the whole factory line to a halt.
Commuters sat in a three-hour jam after the bridge closed.
UsageOften a traffic jam or a paper jam; the stuck thing can also follow of: a jam of logs.
Similarblockage, congestion, gridlock, tailback, snarl
Note
The noun for movement brought to a stop, wherever it happens: a jam on a freeway, a jam of logs in a river, or the elevator jam that National Transportation Safety Board investigators traced in an aircraft's controls.
Checked 2 Nov 2026 · 1 fact
National Transportation Safety Board investigators identified a jam in an aircraft’s elevator flight control system. ntsb.gov
3
stuffverbtransitive
To forcefully push something into a space; to cram or squeeze it in.
Don't jam so many files into one folder.
They jammed twelve people into a car built for five.
UsageYou jam a thing into a space, or a space is jammed with things.
Similarcram, squeeze, stuff, pack, wedge
Note
Here the force is the point: to jam is to push something in roughly, past where it fits easily. George Colman's Farewell Epilogue, spoken in 1779, spells it "Jamm'd in at midnight."
Checked 2 Nov 2026 · 2 facts
George Colman wrote Farewell Epilogue. en.wiktionary.org
The epilogue contains the wording “Jamm'd in at midnight”. en.wiktionary.org
4
get stuckverbintransitive
To become caught or stuck, often within a confined space, so that movement stops.
Cheap zippers tend to jam halfway up.
The rifle jammed after firing only three rounds.
UsageOften get jammed (my foot got jammed); zips, doors and guns simply jam.
Similarstick, seize, catch, lock
Note
The verb at the root of the family, already in use in 1719, when Daniel Defoe has a ship "jaum'd in between two Rocks."
Checked 2 Nov 2026 · 3 facts
The word family begins with a verb expressing pressing or wedging. en.wiktionary.org
The verb was already used in 1719. en.wiktionary.org
Daniel Defoe describes a ship as “jaum'd in between two Rocks” in Robinson Crusoe. en.wiktionary.org
5
casual playingnouncountable
An informal, impromptu performance or rehearsal where musicians play together without much planning.
The late-night jam drew musicians from three different bands.
What started as a casual jam turned into a two-hour set.
UsageOften a jam session.
Similarsession, improvisation
Note
Popular music's word for playing without a script. A jam can be a performance or a rehearsal. What makes it a jam is that the shape is found on the spot, usually over a shared groove or chord pattern rather than written parts. It is the noun beside the verb for playing together loosely, and it stretched to the brainstorming event, where the improvising is done with ideas.
Checked 30 Oct 2026 · 1 fact
The brainstorming-event sense of jam derives from the musical jam session. de.wikipedia.org
6
verbintransitive
To play music informally with others, especially by improvising together without rehearsal.
Old friends still jam together whenever the band reunites.
The guitarist jammed with strangers at the open mic.
UsageWith with or together: jam with strangers, jam together.
Similarimprovise, play, riff
7
tight spotnouncountable
A difficult or troublesome situation, especially one that is hard to escape.
Missing the last train left us in a serious jam.
She got into a financial jam after losing her job.
UsageWith prepositions: in a jam, get into a jam, help someone out of a jam.
Similarfix, trouble, predicament, difficulty, dilemma
Note
Figurative pressure: a jam is a spot you are squeezed into. It sits comfortably in fiction and song, from Upton Sinclair's Boston (1928) to Bob Dylan's "Tangled Up in Blue" (1975). It suits trouble you hope to escape rather than plain hardship.
Checked 2 Nov 2026 · 5 facts
Boston is a novel by Upton Sinclair first published in 1928. gutenberg.org
Boston uses jam to mean a troublesome situation. gutenberg.org
Bob Dylan wrote Tangled Up in Blue. bobdylan.com
Tangled Up in Blue was first released in 1975, on Blood on the Tracks. en.wikipedia.org
Tangled Up in Blue uses jam to mean a troublesome situation. bobdylan.com
8
nouncolloquialcountable
A song or track, especially one regarded as enjoyable or catchy.
That track is a serious jam, so turn it up.
The DJ dropped one classic jam after another.
UsageOften a party jam or a classic jam.
Similartune, banger, anthem, bop
Note
Stretched from the session to what gets played, this jam is any song, usually one you want loud. Jet magazine in 2001 praised "hip-hop-tinged R&B grooves, ballads and party jams." It also invites play with spelling, as in a mix CD called "Summer Jamz 2000."
Checked 2 Nov 2026 · 3 facts
The song sense extends the musical performance or session sense. en.wiktionary.org
Jet used the quoted wording approvingly in 2001. en.wiktionary.org
A mix CD called Summer Jamz 2000 supplies an example of the spelling jamz. en.wiktionary.org
9
verbtransitive
To block something or make it stuck so that it cannot move or work, often 'jam up'.
Heavy downloads can jam up the entire network.
Fallen branches jammed the river and flooded the fields.
Similarblock, clog, choke, obstruct, congest
Oppositeclear, unblock, free
10
block signalsverbtransitive
To interfere deliberately with radio or radar signals, usually by transmitting noise or a stronger signal on the same frequency, so that they cannot be received or read correctly.
Operators can jam enemy radar by flooding the frequency with noise.
The station jammed foreign broadcasts throughout the war.
Similarblock, disrupt
Note
The electronic-warfare verb, and its object can be either end of the link: a government jams broadcasts, and aircraft jam the enemy's radars. Most often noise or a stronger signal on the same frequency drowns out the one the receiver wants, though radar can also be fed false echoes. Unlike the congestion verb, nothing is physically blocked; the wanted signal is simply buried in noise or interference.
Checked 1 Nov 2026 · 4 facts
Governments jam radio broadcasts. en.wikipedia.org
Aircraft jam enemy radars. navair.navy.mil
Radar can be deceived by false echoes. en.wikipedia.org
Electronic jamming interferes with signal reception rather than physically obstructing a passage. en.wiktionary.org
11
brainstorm eventnouncountable
An informal event at which people gather to brainstorm and collaborate on projects.
The studio runs a creative jam every spring to test fresh concepts.
Volunteers at the weekend jam had built a working prototype by Sunday.
UsageWith a noun naming the field: a game jam, an art jam.
Similarhackathon, workshop, brainstorm
Note
Here the musician's improvised session has moved into other kinds of making. It suggests a loose, collaborative burst of work rather than a formal workshop. Fred Patten's Furry Fandom Conventions, 1989–2015 (2017) lists an art jam alongside fursuit games and a nerf war.
Checked 2 Nov 2026 · 3 facts
The collaborative-event sense extends the musical jam-session sense. en.wikipedia.org
Fred Patten wrote Furry Fandom Conventions, 1989–2015, published in 2017. mcfarlandbooks.com
The book lists an art jam alongside fursuit games and a nerf war. en.wiktionary.org

Less common meanings

12
favorite thingnounslangcountable
A thing that a person particularly prefers, desires, enjoys, or cares about.
That old soul record is her jam.
Long hikes through the woods are really his jam.
UsageAfter be with a possessive: that record is her jam. In formal writing it reads as a wink.
Similarthing, bag
Note
It names a personal favorite, so it says nothing about whether the thing is good, only that the speaker loves it. Unlike the British "good luck" sense, it needs an owner.
Checked 2 Nov 2026 · 1 fact
Jam has a British slang sense meaning luck. en.wiktionary.org
13
injure fingerverbtransitive
To injure a finger or toe by catching it in something that closes on it, or by a hard blow to its tip.
She jammed her finger badly when the door slammed shut.
Basketball players often jam their fingers catching hard passes.
Similarstub, crush, pinch, squash
14
be excellentverbcolloquialintransitive
To be of high quality; to be excellent.
The band's latest songs absolutely jam.
This guitar solo really jams.
UsageOften used with a song, track, or solo as the subject: this track jams.
Similarrock, slap, rule
Oppositesuck, stink
15
verbtransitive or intransitive
To dunk a basketball, driving it down through the rim with force.
Tall guards who can jam in traffic are hard to defend.
He jammed the ball so hard the backboard shook.
Similardunk, slam, stuff
16
dunk (basketball)nouncountable
A forceful dunk, in which a player drives the ball down through the basket with power.
The rookie's thunderous jam was the highlight of the game.
He rose above two defenders for a powerful jam.
Similardunk, slam, stuff
Note
Basketball's word for a dunk with force behind it, and the noun beside the verb for dunking. A jam is a dunk as spectacle. The emphasis falls on power, often over a defender, rather than on the two points. It keeps company with words like thunderous and powerful, because the force is part of the meaning, not decoration.
Checked 30 Oct 2026 · 3 facts
A basketball jam is a forceful dunk. en.wiktionary.org
Jam also functions as a verb meaning to dunk. en.wiktionary.org
A dunk scores two points. en.wikipedia.org
17
good fortunenounslangUKcountable or uncountable
Something pleasant, easy, or lucky; good fortune.
The ball bounced off his knee and into the net, and even his own teammates called it a bit of jam.
Winning the raffle twice in a row was nothing but jam.
Similarluck
Note
British slang for luck, best known through its adjective jammy, "lucky." It means luck that simply falls your way rather than luck you earn. Someone may have "more jam than Waitrose," a supermarket joke that plays on the fruit spread.
Checked 2 Nov 2026 · 4 facts
Jam has a British slang sense meaning luck. en.wiktionary.org
Jammy means lucky, especially undeservedly so. en.wiktionary.org
The quoted Waitrose expression is attested as an example of jam meaning luck. en.wiktionary.org
Waitrose is a supermarket chain. en.wikipedia.org
18
pitch insideverbtransitive
In baseball, to pitch the ball in tight on the batter, at or close to the hands.
The veteran jammed the slugger with a fastball on the fists.
Pitchers often jam left-handed hitters to avoid solid contact.
UsageThe batter is the object: jam a hitter, was jammed by the pitch.
Note
A pitch in on the hands can force contact near the bat's handle rather than the barrel. That tends to produce weak grounders, soft fly balls or broken bats, which is the point of jamming.
Checked 2 Nov 2026 · 2 facts
Jamming can produce weak grounders and soft fly balls. mlb.com
Contact near the handle on an inside pitch can break a wooden bat. baseball.physics.illinois.edu
19
climbing holdnouncountable
A climbing maneuver in which a hand, foot, or finger is wedged into a narrow crack to gain a hold.
A solid finger jam was the only way past the smooth section.
He set a fist jam deep in the crack and pulled himself up.
UsageNamed by what goes into the crack: finger jam, fist jam, foot jam.
Note
Climbing keeps the oldest feel of the word, "to be wedged in." It holds because the hand or foot presses outward against the rock rather than gripping an edge. A single crack can demand a whole series of them, so climbers often talk about jams in the plural.
Checked 2 Nov 2026 · 3 facts
The climbing sense preserves the word's earliest meaning of pressing or being wedged in. en.wiktionary.org
Jamming creates a hold through pressure against the crack walls. handbook.alpineclubofcanada.ca
Climbing a single crack can require a sequence of jams. en.wikipedia.org
20
nounslang
Sexual relations, or the thought of them.
21
noun
In roller derby, a play during which points can be scored.
22
verb
In roller derby, to attempt to score points.
23
verbcolloquialCanada
To give up on a date or other joint plan; to stand someone up or chicken out.
24
nounslangCanada
Courage, nerve, or machismo.
25
nounAustralia
The Australian tree Acacia acuminata, valued for its hard, fruity-smelling timber.
26
verb
To steer a ship up into the wind until the wind catches half of her upper sails aback.
It won't do to jam her,” answered Stone ;" but it might be worth findin' out if th' Hope won't lie closer than t' other can." Half a point ----"
Can we date this quote?, William Clark Russell, The Golden Hope
27
noundated
A loose dress or smock worn by young children.

More uses

jam on the brakesto press the brakes suddenly and hard

Practice

Can you tell the meanings of jam apart? Answer 3 quick questions from this page, or write your own sentence and AI will check it.

Origin

First attested in the early 18th century as a verb meaning "to press, be pressed, or be wedged in," and compared to the dialectal jammock ("to press, squeeze, crush into a soft mass"). It is perhaps from Middle English chammen or champen ("to bite, gnash the teeth"), of uncertain origin and probably originally onomatopoeic. The "performance" sense first appears in jazz in 1929, likely a metaphor for "something sweet made by combining many things," influenced by jamboree.

Checked 1 Nov 2026 · 4 facts

The verb is first attested in the early eighteenth century with the stated pressing and wedging meanings. en.wiktionary.org
The etymology compares dialectal jammock, with the stated meanings. en.wiktionary.org
A possible source is Middle English chammen or champen, meaning biting or gnashing the teeth; its origin is uncertain and probably imitative. en.wiktionary.org
The performance sense is first attested in jazz in 1929; the proposed explanation combines a sweetness metaphor with influence from jamboree. en.wiktionary.org