acoustic, or acoustic

& 8. [In Ger akustik; Fr. acoustique; fr. Gr. ἀκουστικός ( akoustikos ) belonging to the sense of hearing; ἀκουστός ( akoustos ) = heard, audible; ἀκούω ( ακουō ) = to hear.] A. As adjective : 1. Anat .: Pertaining to the ear, constituting part of the physical apparatus for hearing. Acoustic duct : The meatus auditor i us, or external pa age of the ear. Acoustic nerves: The same as auditory nerves (q.v.). "... to transmit vibrations to the acoustic nerve." -Darwin: Descent of Man , pt. i., ch. i 2. Med . Designed to act on the ear. Acoustic medicine : One designed to remove some disease of the ear, or to improve defective hearing. (Quincy.) 3. Hist . Obtaining knowledge by the ear. Acoustic Disciples , or Acousmatics . [ACOUSMATIC.] 4. Art : Designed to facilitate hearing or itself to be heard. Pertaining to sound. (See the ex. from Tyndall under ACOUSTICAL.) Acoustic instrument: Generally a synonym for a speaking trumpet. Acoustic ve els: Brazen tubes used in ancient theatres for the purpose of sending the voice of the speaker as far as po ible. In general they succeeded in doing so to the distance of 400 feet. [ACOUSTICS.] B. As substantive : 1. Med .: An acoustic medicine. (See adj ., No. 2.) 2. Hist . (See adj ., No. 3.) a-coustic-al, or a-côus'-tic-al, adj. [ACOUSTIC.] The same as ACOUSTIC (q.v.). " Acoustical experiments on the Seine during the siege of Paris."- Nature, vi. 447. "The sound of the village bell, which comes mellowed from the valley to the traveller upon the hill, has a value beyond its acoustical one." - Tyndall : Frag. of Science , 3rd ed., v. 104.