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

Footage of the jam session has won praise on social media.

From BBC • Jan. 14, 2026

The ride turns into a giant jam session.

From Los Angeles Times • Nov. 14, 2024

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

From New York Times • Mar. 28, 2024

A handful of musicians with violins, guitars and a small harp played an impromptu jam session beneath a tree nearby.

From Seattle Times • Jul. 28, 2023

Allegedly originating during a jam session for the album, Cave co-wrote the song with Mick Harvey.

From Salon • May 18, 2023