Dictograph

[dik-tuh-graf, -grahf]

Trademark.

a brand name for a telephonic device with a highly sensitive transmitter obviating the necessity of a mouthpiece: used for listening to conversations secretly or obtaining a record of them.

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for dictograph

Historical Examples of dictograph

There's only one way to get what we want and that is to use a dictograph.
Spring Street
James H. Richardson
The dictograph, which had been all sound a moment before, was as mute as a cigar-box.
The Silent Bullet
Arthur B. Reeve
Theres a dictograph in the room you occupied, my dear, observed the monocle-man.
Nothing But the Truth
Frederic S. Isham
"The dictograph," I whispered to Rolston, and he pressed my arm to show he understood.
The City in the Clouds
C. Ranger Gull
That was the day she and Dean were planning to put in a dictograph.
The Apartment Next Door
William Andrew Johnston

British Dictionary definitions for dictograph

Dictograph

noun

trademark a telephonic instrument for secretly monitoring or recording conversations by means of a small, sensitive, and often concealed microphone

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for dictograph

Dictograph

patented 1907 in U.S. by K.M. Turner and W. Donnan, from dictation + -graph "instrument for recording; something written."