Assertion: owl's eyelid | /r/Synonym | nictitating membrane
Facets:
Source sentences:
text: The third eyelid is called a nictitating membrane, and is a thin layer of tissue that closes diagonally across the eye, from the inside to the outside.
text: The third eyelid is called a nictitating membrane, and is a thin layer of tissue that closes diagonally across the eye, from the inside to the outside.