Entry 2 senses · 2 variants Webster, 1913

Otacoustic

/(ŏt`ȧ*kous"tĭk [or] ō`tȧ-)/ · Ot·a·cous·tic · IPA

01 a. Assisting the sense of hearing; as, an otacoustic instrument.

1.
Assisting the sense of hearing; as, an otacoustic instrument.

02 n. An instrument to facilitate hearing, as an ear trumpet.

1.
An instrument to facilitate hearing, as an ear trumpet.