A popular joke is told about trombonists:
 
Q: What do you call a beautiful woman on a trombonist’s arm?
A: A tattoo.
 
The trombonist version has been told since at least 2000, but same joke has also been told about drummers and other musicians.
 
 
Google Groups: rec.music.artists.kings-x
More musician jokes
amwatts
10/12/00
(...)
Q: What do you call a beautiful woman on a trombonist’s arm?
A: A tattoo.
 
Google Groups: alt.music.trombone
A bit of trombone humoUr
Don Dale
10/19/00
(...)
Q: What do you call a beautiful woman on a trombonist’s arm?
A: A tattoo.
 
Google Groups: alt.music.hammond-organ
[HAM] Humour
Scott Hawthorn
11/16/00
(...)
Q: What do you call a beautiful woman on a percussionist’s arm?
A: A tattoo.
 
Google Groups: alt.guitar.beginner
Guitar News Weekly #149 - July 2, 2001
Geoff
7/2/01
(...)
Q: What do you call a beautiful woman on a lead guitarist’s arm?
A: A tattoo.
 
Google Groups: rec.music.makers.guitar.acoustic
DRUMMER JOKES
J.W.Beasley
10/12/01
(...)
What do you call a beautiful woman on the arm of a drummer?
A tattoo!
 
Google Books
Phil Spector:
Out of His Head
By Richard Williams
London: Omnibus
2003
Pg. 186:
And then, strangely, Spector’s friends began reporting that he had stopped returning their calls, stopped sending silly e-mails full of musicians’ jokes (“What do you call a beautiful woman on a trombonist’s arm?” “A tattoo”), stopped communicating altogether.
 
Google Groups: alt.banjo
How bout some funnies??
Tim
4/4/04
(...)
What do you call a beautiful woman on a Banjo Player’s arm?
A tattoo.
 
Google Books
Grumpy Old Git Jokes:
Because life’s not all fun, fun, fun
By Ian Allen
London: Portico Books
2014
Pg. ?:
What do you call a beautiful woman on a trombonist’s arm?
A tattoo.