jam session: Meaning and Definition of

jam' ses"sion

Pronunciation: [key]
  1. a meeting of a group of musicians, esp. jazz musicians, to play for their own enjoyment.
  2. an impromptu jazz performance or special performance by jazz musicians who do not regularly play together. Also called
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.