A trombone with a bassoon reed in place of the usual brass mouthpiece. (Something like thick tape must be wrapped around the tube of the reed so it will fit snugly inside the place where the mouthpiece goes.) Used by P.D.Q. Bach in his "Serenude" and "The Seasonings". Other instruments in this family include the "trumpoe", a trumpet with an oboe reed, and the "international horn", a french horn with an english horn reed. (All right, I confess, I made those up. But the tromboon is real! I swear!)