What do you call a trombonist with a 5-year diary?
An optimist.
What's the definition of a gentleman?
Someone who can play the trombone but doesn't!
How can you tell which is the trombonist's kid at the playground?
It's the one who can't work out how to swing and doesn't understand what
the slide is for.
If you see a trombonist and a conductor in the middle of the road, which
one should you aim for?
The conductor: Business before pleasure!
The best line in the world about trombone players comes from The
Mikado, but W.S.Gilbert and A.S.Sullivan. Nanki-Poo, the son of the
Emperor of Japan has run away from the palace and is hiding out as a
member of the town band. There he meets the love of his life,
Yum-Yum...
Nanki-Poo: "And I, disguised as a second trombone..."
Yum-Yum: "I knew you were not a musician the moment you began to play!"