'Ptosis' definitions:
Definition of 'ptosis'
(from WordNet)
noun
Drooping of the upper eyelid caused by muscle paralysis and weakness
Definition of 'Ptosis'
From: GCIDE
- Ptosis \Pto"sis\ (t[=o]"s[i^]s), n. [NL., fr. Gr. ptw^sis a falling.] (Med.) Drooping of the upper eyelid, produced by paralysis of its levator muscle. [1913 Webster]