conjunctiva
noun [ C usually singular ] anatomy specialized uk/ˌkɒn.dʒʌŋkˈtaɪ.və/ us/ˌkɑːn.dʒəŋkˈtaɪ.və/
结膜（覆盖眼睑内部和眼球前方表面的一层透明黏膜）
the transparent layer of mucous membrane that covers the inside of the eyelid and the front surface of the eyeball