galvanoscope
noun
gal·va·no·scope gal-ˈva-nə-ˌskōp 
ˈgal-və-nə-
ˈgal-və-nə- : an instrument for detecting the presence and direction of an electric current by the deflection of a magnetic needle
Word History
Etymology
borrowed from French, from galvano- (in galvanomètre galvanometer) + -scope -scope
First Known Use
1832, in the meaning defined above
Medical Definition
galvanoscope
noun
gal·va·no·scope gal-ˈvan-ə-ˌskōp ˈgal-və-nə-
ˈgal-və-nə- : an instrument for detecting the presence and direction of an electric current by the deflection of a magnetic needle