A trombonist is a person who plays the trombone — that is the word itself, whatever the line above says. The trombone is the large brass instrument you play by blowing into a mouthpiece and sliding a long tube in and out to change the notes, so a trombonist is the player of that instrument, whether in an orchestra, a jazz band, a marching band or a school music room. The word is neutral and slightly formal: it is what you would read in a concert programme, a newspaper review, or a job advertisement for an orchestra. In everyday speech people very often say trombone player instead, and that is perfectly good English — "my brother's a trombone player" sounds more natural in conversation than "my brother's a trombonist." The word says nothing about how good the person is or whether they are paid; a beginner in a school band is a trombonist too. English builds many musician words this way, so if you learn the pattern here you get a whole set of words free. Note that the word covers only the player, not the instrument — for the object itself you need trombone.

長號手、伸縮號演奏者（就是吹長號的人，不是樂器本身）。