The Collaborative International Dictionary
Cymoscope
Cymoscope \Cy"mo*scope\, n. [Gr. ? wave + -scope.] (Elec.) Any device for detecting the presence of electric waves. The influence of electric waves on the resistance of a particular kind of electric circuit, on the magnetization of steel, on the polarization of an electrolytic cell, or on the electric condition of a vacuum has been applied in the various cymoscopes.
Wiktionary
cymoscope
n. (context wireless telegraphy disused English) A (l en detector) of (l en electromagnetic) (l en wave waves).