[1] : The Collaborative International Dictionary of English v.0.48

zona \zo"na\, n.; pl. zonae. l., a girdle. see zone.
   a zone or band; a layer.
   1913 webster

   zona pellucida. nl. biol.
   a the outer transparent layer, or envelope, of the ovum. it
       is a more or less elastic membrane with radiating striae,
       and corresponds to the cell wall of an ordinary cell. see
       ovum, and illust. of microscope.
   b the zona radiata.

   zona radiata nl. biol., a radiately striated membrane
      situated next the yolk of an ovum, or separated from it by
      a very delicate membrane only.
      1913 webster
see also:
zonae zone zona pellucida ovum microscope zona radiata 

Zonae >> Z Words
Zonae, definition of term: Zonae
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