Webster’s Revised Unabridged Dictionary · 1913
Oscillograph
Os′cil·lo·graph, n. [L. oscillare to swing + -graph.] (Elec.) An apparatus for recording or indicating alternating-current wave forms or other electrical oscillations, usually consisting of a galvanometer with strong field, in which the mass of the moving part is very small and frequency of vibration very high. — Os′cil·lo·graph′ic (#), a.