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nictitating membrane

noun

Definition of nictitating membrane

: a thin membrane found in many vertebrates at the inner angle or beneath the lower lid of the eye and capable of extending across the eyeball

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First Known Use of nictitating membrane

1713

in the meaning defined above

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Medical Dictionary

nictitating membrane

noun

medical Definition of nictitating membrane

: a thin membrane found in many vertebrate animals at the inner angle or beneath the lower lid of the eye and capable of extending across the eyeball — called also membrana nictitans, third eyelid

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nictitating membrane

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