Lewis & Short

ācrŏāsis, is, f., = ἀκρόασις (a hearing, a listening to), the discourse delivered before an assembly, public lecture (cf. the use of contio among Eng. and collegium among Germ. scholars, for discourse, etc.): ut eas vel in acroasi audeam legere, in a public lecture, Cic. Att. 15, 17, 2: Callias acroasin fecit, Vitr. 10, 22: plurimas acroases fecit, Suet. Gram. 2 (al. ἀκροάσεις).