Word Study
electroscope
CIDE DICTIONARY
electroscope, n. [Electro- + -scope: cf. F. électroscope.].
An instrument for detecting the presence of electricity, or changes in the electric state of bodies, or the species of electricity present, as by means of pith balls, and the like. [1913 Webster]
OXFORD DICTIONARY
electroscope, n. an instrument for detecting and measuring electricity, esp. as an indication of the ionization of air by radioactivity.
Derivative
electroscopic adj.
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