n.
The thick, solid, transparent outer membrane of a developed mammalian ovum. Also called oolemma.
[New Latin zōna pellūcida : Latin zōna, belt, girdle + Latin pellūcida, feminine of pellūcidus, transparent.]
The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.