Eye"stone` (ī"stōn`), n.
1. A small, lenticular, calcareous body, esp. an
operculum of a small marine shell of the family
Turbinidæ, used to remove a foreign substance from the
eye. It is put into the inner corner of the eye under the lid, and
allowed to work its way out at the outer corner, bringing with it the
substance.
2. (Min.) Eye agate. See under
Eye.