Jew's harp
or Jews' harp
noun
(sometimes lowercase)
a small, simple musical instrument consisting of a lyre-shaped metal frame containing a metal tongue, which is plucked while the frame is held in the teeth, the vibrations causing twanging tones.
Origin of Jew's harp
First recorded in 1585–95; perhaps jocular; earlier called
Jew's trump
British Dictionary definitions for jew's-harp
jew's-harp
noun
a musical instrument consisting of a small lyre-shaped metal frame held between the teeth, with a steel tongue plucked with the finger. Changes in pitch are produced by varying the size of the mouth cavities