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zizz
zloty
zm
Zmodem
Zn
zo
zo-
zoarium
zod.
zodiac
zodiacal constellation
zodiacal light
zoetrope
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zona pellucida
zo·na pel·lu·ci·da [ znə pə lssidə ]


noun 
Definition:
 
layer enclosing egg cell: a thick transparent envelope that surrounds a developing ovum, allowing only one sperm cell through to fertilize the ovum
[< modern Latin, "transparent band"]
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