Originally a Buddhist term for purifying the six sensory organs (eyes, ears, nose, tongue, body, and mind); now describes being completely free from worldly attachments and desires.

To have one's ears pure and peaceful; to be in a quiet place free from noisy chatter or nagging; to stay away from the filth and unrest of the world or to be undisturbed by troublesome matters

a device used for cleaning or purifying, such as an air or water purifier; a clarifying apparatus