phonautograph noun.
[fǝ'nɔ:tǝgrɑ:f] M19.[French phonautographe, formed as PHONO- + AUTO-1 + -GRAPH.]Hist. An apparatus for automatically recording sound vibrations in the form of a tracing on a revolving cylinder.
■ phonauto'graphic adjective L19. ■ phonauto'graphically adverb by means of a phonautograph
L19. [TahlilGaran] English Dictionary ▲