Dictograph
Pronunciation : Dic"to*graph
Part of Speech : n.
Definition : Defn: A telephonic instrument for office or other similar use, having a sound-magnifying device enabling the ordinary mouthpiece to be dispensed with. Much use has been made of it for overhearing, or for recording, conversations for the purpose of obtaining evidence for use in litigation.
The makers of this instrument spell it dictograph.
[L. dictum a thing said + E. -graph.]
Source : Webster's Unabridged Dictionary, 1913