WordReference Random House Learner's Dictionary of American English © 2014
trom•bone /trɑmˈboʊn, ˈtrɑmboʊn/USA pronunciation
Music and Dancea musical wind instrument consisting of a rounded metal tube expanding into a bell and bent twice into aUshape, and having a slide for varying the tone.
Collins Concise English Dictionary © HarperCollins Publishers::
trombone /trɒmˈbəʊn/ n
Etymology: 18th Century: from Italian, from tromba a trumpet, from Old High German trumbatromˈbonist n
- a brass instrument, a low-pitched counterpart of the trumpet, consisting of a tube the effective length of which is varied by means of a U-shaped slide. The usual forms of this instrument are the tenor trombone (range: about two and a half octaves upwards from E) and the bass trombone (pitched a fourth lower)
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