Word Study
ptosis
WORDNET DICTIONARY
Noun ptosis has 1 sense
CIDE DICTIONARY
ptosis, n. [NL., fr. Gr. a falling.].
Drooping of the upper eyelid, produced by paralysis of its levator muscle. [1913 Webster]
OXFORD DICTIONARY
ptosis, n. a drooping of the upper eyelid due to paralysis etc.
Derivative
ptotic adj.
Etymology
Gk ptosis f. pipto fall
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