mydriasis

noun

my·​dri·​a·​sis mə-ˈdrī-ə-səs How to pronounce mydriasis (audio)
: excessive or prolonged dilatation of the pupil of the eye
mydriatic adjective or noun

Examples of mydriasis 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.
Dilated pupils—called mydriasis—range from 4 to 8 millimeters in size.4 Your pupils also constrict slightly to look at close objects and dilate slightly to look far away. Troy Bedinghaus, Od, Verywell Health, 17 July 2023

Word History

Etymology

Latin, from Greek

First Known Use

1684, in the meaning defined above

Time Traveler
The first known use of mydriasis was in 1684

Dictionary Entries Near mydriasis

Cite this Entry

“Mydriasis.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/mydriasis. Accessed 21 Dec. 2024.

Medical Definition

mydriasis

noun
my·​dri·​a·​sis mə-ˈdrī-ə-səs How to pronounce mydriasis (audio)
plural mydriases -ˌsēz How to pronounce mydriasis (audio)
: excessive or prolonged dilation of the pupil of the eye
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