Harmonica

From DictionGloss

A small, hand-held wind instrument on which tones are produced by exhaling and inhaling into recessed air slots. In the Appalachian South, the harmonicas play an ordinary diatonic scale but not the "chromatic" intervals between the diatonic scale tones. They are thus sold in separate models to play in different keys, and some musicians keep multiple harmonicas (a G-harmonica, a C-harmonica, a D-harmonica, and so forth) in order to play with other instruments. Also known as French harp.