Emily Dickinson Lexicon

A-COUS'TIC, a. [Gr. ακουστικος, from ακουω, to hear.]

Pertaining to the ears, to the sense of hearing, or to the doctrine of sounds. Acoustic duct, in anatomy, the meatus auditorius, or external passage of the ear. Acoustic vessels, in ancient theaters, were brazen tubes or vessels, shaped like a bell, used to propel the voice of the actors, so as to render them audible to a great distance; in some theaters at the distance of 400 feet. – Encyc. Acoustic instrument, or auricular tube, called in popular language, a speaking-trumpet. – Encyc. Acoustics, or Acousmatics, was a name given to such of the disciples of Pythagoras as had not completed their five years probation.