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zona pellucida

[zoh-nuh puh-loo-si-duh, pel-yoo-]
noun, plural zo·nae pel·lu·ci·dae [zoh-nee puh-loo-si-dee, pel-yoo-] /ˈzoʊ ni pəˈlu sɪˌdi, pɛlˈyu-/. Anatomy.
  1. the transparent, noncellular layer surrounding the ovum of mammals, often having radial striations.

Origin of zona pellucida

From New Latin, dating back to 1835–45; see origin at zone, pellucid
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
zona pellucida in Medicine

zona pellucida

[pə-lōō′sĭ-də]
n.
  1. The thick solid transparent outer membrane of a developed mammalian ovum.oolemma
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.