Dictograph

American  

[dik-tuh-graf, -grahf] / ˈdɪk təˌgræf, -ˌgrɑf /

Trademark.

1. 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.

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Dictograph British  

/ ˈdɪktəˌɡrɑːf, -ˌɡræf /

noun

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

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Example Sentences

Colonel Schick sued Dictograph for infringement of patent.

From Time Magazine Archive

Well, Dictaphone just isn't that kind of machine and Dictograph, a trademarked voice-transmitting device, isn't really used by criminal investigators, local or federal, to overhear remote conversations.

From Time Magazine Archive

Announced for early marketing by both Dictograph Products Co.,

From Time Magazine Archive

At the federal penitentiary in Danbury, Conn., for example, Dictograph Products Inc. sponsors a training program for microsoldering hearing aids, hires the trained convicts after their release.

From Time Magazine Archive

This would explain why the Dictograph set up by the private detectives working for Mollie Burkhart’s family had never picked up any incriminating statements, and why Rose’s clothes had never been found in the creek.

From "Killers of the Flower Moon" by David Grann