exophthalmos

noun

ex·​oph·​thal·​mos ˌek-säf-ˈthal-məs How to pronounce exophthalmos (audio)
-səf-,
-säp-
variants or less commonly exophthalmus
: abnormal protrusion of the eyeball
exophthalmic
ˌek-säf-ˈthal-mik How to pronounce exophthalmos (audio)
-səf-
-säp-
adjective

Examples of exophthalmos in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
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, 19 Oct. 2017

Word History

Etymology

New Latin, from Greek exophthalmos having prominent eyes, from ex out + ophthalmos eye

First Known Use

1872, in the meaning defined above

Time Traveler
The first known use of exophthalmos was in 1872

Browse Nearby Words

Cite this Entry

“Exophthalmos.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/exophthalmos. Accessed 7 Nov. 2025.

Medical Definition

exophthalmos

noun
ex·​oph·​thal·​mos
variants also exophthalmus
: abnormal protrusion of the eyeball
exophthalmic adjective

More from Merriam-Webster on exophthalmos

Last Updated: - Definition revised
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