Blepharocoloboma

A rare congenital condition where part of the eyelid is missing or incompletely formed, creating a gap or notch in the eyelid margin.

From Greek 'blepharon' (eyelid) + 'koloboma' (from 'koloboun', meaning to curtail or amputate). Colobomas are congenital tissue defects first systematically described in the 19th century, with the eyelid being one possible location.