IPA: /ˈdaɪəˌfoʊn/
KK: /daɪəˌfoʊn/
A type of sound-producing device that creates sound by using a slotted piston moved by compressed air, often used as a fog signal that emits two tones.
The diaphone sounded through the fog, warning ships of the nearby coast.
Diaphone is formed from "dia-" (meaning through) and "phone" (from Greek "phonē", meaning sound or voice). The word refers to a device that produces sound through a specific mechanism, often used in signaling or alarms.
Think of 'through' ('dia-') and 'sound' ('phone') to remember that a diaphone is a device that produces sound through a particular method.