Aural, auricular, audible mean heard or perceived by the ear but they are not often interchangeable.
Aural is applicable to any sensation or impression which affects the auditory sense rather than other senses.
Auricular is applicable not only to what is heard as distinguished from what is read but also especially to something communicated privately and addressed to the ear of a particular person; thus, auricular confession is used of the private confession of sins to a priest as distinguished from open confession before a congregation.
Audible is applicable only to sounds, voices, or conversations which are heard as distinguished from those which are not heard because too faint, too low, or uttered in a whisper.