Phonoscope
Pronunciation : Pho"no*scope
Part of Speech : n.
Etymology : [Phono- + -scope.] (Physics) (a) An instrument for observing or exhibiting the motions or properties of sounding bodies; especially, an apparatus invented by K?nig for testing the quality of musical strings. (b) An instrument for producing luminous figure
Source : Webster's Unabridged Dictionary, 1913