zo·na pel·lu·ci·da 
(zōnə pə-lsĭ-də, pĕl-y-)
(zōnə pə-lsĭ-də, pĕl-y-)n.
A thick transparent extracellular coat that surrounds the mammalian ovum and is composed of glycoproteins. Spermatozoa bind to the zona pellucida during fertilization.
[New Latin zōna pellūcida : Latin zōna, belt, girdle + Latin pellūcida, feminine of pellūcidus, transparent.]