noun (1)
\ˈjam \

Definition of jam 

(Entry 1 of 4)

: a food made by boiling fruit and sugar to a thick consistency


jammed; jamming

Definition of jam (Entry 2 of 4)

intransitive verb

1a : to become blocked, wedged, or stuck fast The line jammed and the boat hung useless.

b : to become unworkable when a movable part becomes blocked or stuck the gun jammed

2 : to force one's way into a restricted space People continued to jam into the already crowded hall.

3 : to improvise on a musical instrument with a group : to take part in a jam session musicians jamming together

4 basketball : dunk sense 2

transitive verb

1a : to press into a close or tight position jammed his hat on

b(1) : to cause to become wedged or stuck so as to be unworkable jam the typewriter keys

(2) : to make (machinery) unworkable by becoming wedged or stuck The paper jammed the printer.

c : to block passage of : obstruct traffic jammed by an accident

d : to fill often to excess : pack the crowd jammed the theater

2 : to push forcibly jammed the shovel into the ground especially : to apply (brakes) suddenly and forcibly used with on suddenly jammed on the brakes

3 : to cause (a part of the body) to be painfully crushed or squeezed jammed his finger in the door

4a : to make unintelligible by sending out interfering signals or messages jam a radio broadcast

b : to make (a radar apparatus) ineffective by sending out interfering signals or by causing reflection of radar waves trying to jam the enemy's radar

5 football : to block, crowd, or bump (a pass receiver) near the line of scrimmage The receiver got jammed at the line.

6 baseball : to pitch inside to (a batter) jammed him with a fastball


noun (2)

Definition of jam (Entry 3 of 4)

1a : a crowded mass that impedes or blocks movement a traffic jam

b : an act or instance of becoming blocked or jammed (see jam entry 2) paper causing a jam of the copier

2a : the quality or state of being blocked, stopped, or jammed the jam of the legislature caused by the piling up of new bills in the final days

b : the pressure or congestion of a crowd : crush a jam of people

3 : a difficult situation or state of affairs : fix got into a jam

5 basketball : dunk shot

6 slang : a musical piece

Definition of Jam (Entry 4 of 4)


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Other Words from jam

Noun (1)

jammy \ ˈja-​mē \ adjective


jammer \ ˈja-​mər \ noun

Synonyms & Antonyms for jam

Synonyms: Verb

brim, charge, cram, fill, heap, jam-pack, load, pack, stuff

Antonyms: Verb

clear, empty, evacuate, vacate, void

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Examples of jam in a Sentence


Thousands of people jammed into the hall. People were jamming the exits after the concert. He jammed the book back into the bookcase. She jammed her foot down hard on the brakes. She jammed on the brakes. A piece of paper jammed the copy machine.
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First Known Use of jam

Noun (1)

circa 1736, in the meaning defined above


1706, in the meaning defined at intransitive sense 1a

Noun (2)

1805, in the meaning defined at sense 1b

History and Etymology for jam

Noun (1)

probably from jam entry 2


origin unknown

Noun (2)

see jam entry 2

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Time Traveler for jam

The first known use of jam was in 1706

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More Definitions for jam



English Language Learners Definition of jam

: to fill (a place) completely

: to fill (something, such as a door or a road) so that movement is slow or stopped

: to press or push (an object) into a tight place


\ˈjam \
jammed; jamming

Kids Definition of jam

 (Entry 1 of 3)

1 : to crowd, squeeze, or wedge into a tight position Fans jammed the auditorium.

2 : to put into action hard or suddenly He jammed his hands into his pockets. She jammed on the brakes.

3 : to hurt by pressure I jammed a finger in the car door.

4 : to be or cause to be stuck or unable to work because a part is wedged tight Paper jammed the copier.

5 : to cause interference in (radio or television signals)



Kids Definition of jam (Entry 2 of 3)

: a food made by boiling fruit with sugar until it is thick



Kids Definition of jam (Entry 3 of 3)

1 : a crowded mass of people or things that blocks something a traffic jam

2 : a difficult situation I got myself into a jam.

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Comments on jam

What made you want to look up jam? Please tell us where you read or heard it (including the quote, if possible).


obstinately defiant of authority

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