Quantcast
Merriam-Webster Logo
  • Dictionary
  • Thesaurus
  • Scrabble
  • Spanish Central
  • Learner's Dictionary

ptosis

play
noun pto·sis \ˈtō-səs\

Definition of ptosis

plural

ptoses

play \-ˌsēz\
  1. :  a sagging or prolapse of an organ or part; especially :  a drooping of the upper eyelid



Origin and Etymology of ptosis

New Latin, from Greek ptōsis act of falling, from piptein


First Known Use: 1743


Medical Dictionary

ptosis

play
noun pto·sis \ˈtō-səs\

Medical Definition of ptosis

plural

ptoses

\-ˌsēz\play
  1. :  a sagging or prolapse of an organ or part <renal ptosis>; especially :  a drooping of the upper eyelid (as from paralysis of the oculomotor nerve)




Learn More about ptosis

  1. Medical Dictionary: Definition of ptosis Britannica.com: Encyclopedia article about ptosis


Seen and Heard

What made you want to look up ptosis? Please tell us where you read or heard it (including the quote, if possible).

WORD OF THE DAY

in the capacity or character of

Get Word of the Day daily email!

WORD GAMES

Take a 3-minute break and test your skills!

fox-in-summer-forest

Which of these is a synonym of inchoate?

frightening massive experimental formless
Name That Thing

Test your visual vocabulary with our 10-question challenge!

TAKE THE QUIZ
SCRABBLE® Sprint

Test Your Knowledge - and learn some interesting things along the way.

TAKE THE QUIZ