third eyelid

noun

1. nictitating membrane.

third eyelid

noun

1. another name for nictitating membrane

Example Sentences

The surgery was complicated by the unique characteristics of penguins, such as a third eyelid, which protects their eyes underwater but had a tendency to close during the surgery.

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His daughter searched for information online and learned about a membrane, or third eyelid, that protects the birds’ peepers in-flight and on fishing expeditions.

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But the third eyelid actually plays an important role in maintaining the eye's health.

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A third eyelid, between the regular eyelids and the cornea, protects the globe and also has a gland at the bottom that produces extra tears.

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The eye is provided with a nictitating membrane or third eyelid, at the base of which open the ducts of the Harderian gland.

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