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nictitating membrane

noun

Definition of nictitating membrane

  1. :  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



1713

First Known Use of nictitating membrane

1713


Medical Dictionary

nictitating membrane

noun

Medical Definition of nictitating membrane

  1. :  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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