phoneidoscope

English

Etymology

phono- +‎ Ancient Greek εἶδος (eîdos, “sight”) +‎ -scope

Noun

phoneidoscope (plural phoneidoscopes)

Figures on film in a phoneidoscope

1. An instrument for studying the motions of sounding bodies by optical means. It consists of a tube across whose end is stretched a film of soap solution thin enough to give coloured bands, whose form and position are affected by sonorous vibrations.

Part or all of this entry has been imported from the 1913 edition of Webster’s Dictionary, which is now free of copyright and hence in the public domain. The imported definitions may be significantly out of date, and any more recent senses may be completely missing.
(See the entry for “phoneidoscope”, in Webster’s Revised Unabridged Dictionary, Springfield, Mass.: G. & C. Merriam, 1913, →OCLC.)