prop·​to·​sis | \ präp-ˈtō-səs How to pronounce proptosis (audio) , prō-ˈtō- How to pronounce proptosis (audio) \

Definition of proptosis

: forward projection or displacement especially of the eyeball

Examples of proptosis in a Sentence

Recent Examples on the Web Bulging or protruding eyes (proptosis or exophthalmos) can be a sign of Graves disease, a disorder causing overactivity of the thyroid gland (hyperthyroidism). Claire Gillespie, SELF, "5 Reasons to Get Your Eyes Checked That Have Nothing to Do With Your Vision," 19 Oct. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'proptosis.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of proptosis

1676, in the meaning defined above

History and Etymology for proptosis

New Latin, from Late Latin, falling forward, from Greek proptōsis, from propiptein to fall forward, from pro- forward + piptein to fall — more at pro-, feather

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The first known use of proptosis was in 1676

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Cite this Entry

“Proptosis.” Dictionary, Merriam-Webster, Accessed 24 Nov. 2020.

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More Definitions for proptosis


pro·​pto·​sis | \ (ˈ)prō-ˈtō-səs How to pronounce proptosis (audio) , präp-ˈtō- How to pronounce proptosis (audio) \
plural proptoses\ -​ˌsēz How to pronounce proptoses (audio) \

Medical Definition of proptosis

: forward projection or displacement especially of the eyeball

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