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hippus

noun

hip·​pus ˈhip-əs How to pronounce hippus (audio)
: a spasmodic variation in the size of the pupil of the eye caused by a tremor of the iris

Cite this Entry

“Hippus.” Merriam-Webster.com Medical Dictionary, Merriam-Webster, https://www.merriam-webster.com/medical/hippus. Accessed 1 Dec. 2025.

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