atrium

(a’tre-um), pl. a’fris [L. “hall"]. 1. An auricle of the heart. 2. The main part of the tympanic chamber, situated below the head of the malleus. a. dex’trum, the right auricle. infection-a., the point of entrance of a bacterial disease into the system. a. laryn’gis, that part of the larynx which lies above the false vocal cords. left a., the left auricle. right a., the right auricle. a. sin is’trum, the left auricle. a. vagi’n®, the vestibule of the vagina.