Green’s Dictionary of Slang

1. a jazz musician.

1918		Kansas City Sun (MO) 18 May 6/5: The good jazzer can take any sorgt of a melody and jazz it up [...] He plays all the convolutions, evolutions and variations.
1919		Current Opinion Aug. 99/3: The ‘klaxon’ in particular [...] as one of the Jazzers explains, [...] reminds them that they have an automobile [DA].
1921		Morn. Tulsa Daily World (OK) 30 Apr. 9/1: Dancing 8.45 to 11.45 [to] Miller’s Jazz-ola Jazzers.
1929		Etude Sept. 655/2: But the jazzists have woven some novel patterns with the rhythmic threads [DA].
1932		Forum Apr. 235/2: The jazzers, weary of the stenciled refrain [...] have made up their mind to break through this cage [DA].
1941		New Yorker 1 Mar. 44/2: Basie makes effective use of tone-shading, a technique which some of our noisier jazzists might do well to cultivate [DA].
1999		Guardian Rev. 1 Oct. 25: There’s a certain type of person attracted to being a jazzer and whatever style they like they want their music not to follow everybody else’s.
2000		Guardian G2 23 Feb. 12: The trials and tribulations of male jazzers in New York, from the 50s heyday to the 80s nadir.

2. a jazz fan.

1919		Noble Sissle ‘Jazzola’ 🎵 Come, jazzers, gather ’round, / Jazz lovers from every town.
1922		Ogden Standard-Examiner (UT) 12 Mar. 2/1: A tenor singing in the manner of Al Jolson, and a balle that shimmies, isn’t just the jazz dream of a jazz-mad jazzer.
1966		M. Rumaker Exit 3 and Other Stories 143: He’s a jazzer.
2004		(con. 1960s-70s) T. Taylor Top Fellas 15/2: We’d hang around a jazz club in Newport [...] just to pick fights and hang shit on the jazzers.

3. a party goer.

1922

S.V. Benét Young People’s Pride 207: He babbled with the returning jazzers for a quarter of an hour.