1911 Encyclopædia Britannica/Auricle

AURICLE (from Lat. diminutive of auris, ear), the external ear in animals, or an analogous part in plants, &c. From a supposed resemblance to the ear of a dog, the term was applied to the upper cavities of the heart. The adjective “auricular” is more specially used in the phrase “auricular confession” (see Confession), i.e. private.