Definition of photophone in English:

photophone

noun

historical
  • 1Telecommunications. An instrument for transmitting sound by means of light; specifically that invented by Alexander Graham Bell and Sumner Tainter in 1880.

  • 2Film. A system for producing synchronized soundtracks on films. Now disused.

Origin

Late 19th century; earliest use found in Alexander Graham Bell (1847–1922), teacher of deaf people and inventor of the telephone. From photo- + -phone.

Pronunciation

photophone

/ˈfəʊtəʊfəʊn/