sphincter pupillae

Show Summary Details

Quick Reference

The muscle that expands the iris and thereby constricts the pupil of the eye. Compare dilator pupillae. [From Greek sphinkter a tightener, from sphingein to bind tight + Latin pupillae of the pupil, from pupilla a pupil, diminutive of pupa a girl or a doll, alluding to the tiny reflection in the eye]

Subjects: Psychology.

Reference entries

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.