jam session

American  

[jam sesh-uhn] / ˈdʒæm ˌsɛʃ ən /

noun

1. Music.

   1. a meeting of a group of musicians, especially jazz musicians, to improvise, experiment, or play for their own enjoyment.

   2. an impromptu musical performance, especially of jazz.

   3. a special performance by musicians, especially jazz musicians, who do not regularly play together.

2. an informal, freely collaborative meeting, conference, or discussion.

   The event was a laid-back jam session for creatives to get together and network.

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jam session British  

noun

1. slang an unrehearsed or improvised jazz or rock performance

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Etymology

Origin of jam session

First recorded in 1930–35; perhaps jam ¹, or shortening of jamboree

Example Sentences

See Examples For:

jam session

Twenty years ago, while still an undergraduate at the Juilliard School of Music—before his seven seasons as bandleader for “The Late Show With Stephen Colbert” or his eight Grammy Awards—Jon Batiste attended a jam session.

From The Wall Street Journal ● Aug. 19, 2026

He said as Morrison was leaving at the end of their jam session he said: "Nice voice, nice songs, blah, blah, blah."

From BBC ● Jul. 30, 2026

From the beginning, her style has always been instinctual; a freeform jam session where she sits at the piano or with her guitar and just lets her ideas flow out.

From Los Angeles Times ● Oct. 27, 2025

“On the Adamant” is like a jam session, too — a jumble of bright spots and tedious meanderings.

From New York Times ● Mar. 28, 2024

But it was during this first jam session that they realized how well they complement one another and discovered their shared love of wide-ranging musical taste, especially musical theater.

From Los Angeles Times ● Dec. 11, 2023