Entropium, or ENTROPION (Gr. en, 'in,' and trepō, 'I turn'), inversion of the edge of the eyelid, consequent either on loss of substance on its inner surface, or on excessive action of the muscle (the orbicularis palpebrarum) which closes the lids. The eyelashes are turned inwards and rub upon the globe during the movements of the lids, producing much irritation, and sometimes opacity of the cornea. Temporary relief may be obtained by plucking out the misdirected lashes by the roots; but the radical cure of severe entropium requires a careful adaptation of the surgeon's art to the circumstances of the particular case, and should not be attempted by unskilled hands. The most common cause of entropium is granular conjunctivitis. See EYE (DISEASES OF).