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epiboly

[ih-pib-uh-lee]
noun, plural e·pib·o·lies. Embryology.
  1. the movement and spreading out of cells into sheets of tissue that overlie or surround other groups of cells, especially as in the formation of certain gastrulas.

Origin of epiboly

1870–75; < Greek epibolḗ a throwing on, equivalent to epi- epi- + bol- (variant stem of bállein to throw) + -ē noun suffix
Related formsep·i·bol·ic [ep-uh-bol-ik] /ˌɛp əˈbɒl ɪk/, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for epiboly

epiboly

noun plural -lies
  1. embryol a process that occurs during gastrulation in vertebrates, in which cells on one side of the blastula grow over and surround the remaining cells and yolk and eventually form the ectoderm
Derived Formsepibolic (ˌɛpɪˈbɒlɪk), adjective

Word Origin for epiboly

C19: from Greek epibolē a laying on, from epiballein to throw on, from epi- + ballein to throw
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
epiboly in Medicine

epiboly

[ĭ-pĭb′ə-lē]
n.
  1. The growth of a rapidly dividing group of cells around a more slowly dividing group of cells, as in the formation of a gastrula.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.