Ot`a*cous"tic (?), a. [Oto- + acoustic: cf. F. otacoustique.]
Assisting the sense of hearing; as, an otacoustic instrument.
© Webster 1913.
Ot`a*cous"tic (?), Ot`a*cous"ti*con (?), n.
An instrument to facilitate hearing, as an ear trumpet.
© Webster 1913.