Jazz musicians have added many new terms to the musical dictionary.
Tune - A song or composition which is used as the basis for improvisation.
Changes - The underlying chord progression of a song (a series of chord changes).
Head - The melody of a song, usually played at the start and finish, with solos in between.
Chorus - Once through the entire form of the piece.
Bridge - The B Section or "middle eight'.
Blowing - Improvising, taking a solo.
Trading Fours - Musicians taking turns to improvise four bar phrases.
Bop - Bebop style (e.g. Charlie Parker, Dizzy Gillespie, Thelonious Monk).
There are many more such terms, but these but these will help you out in Jam sessions.