The growth of a rapidly dividing group of cells around a more slowly dividing group of cells, as in the formation of a gastrula.
[Greek epibolē, a throwing or laying on, from epiballein, to throw on : epi-, epi- + ballein, to throw; see gwelə- in the Appendix of Indo-European roots.]
ep′i·bolic (ĕp′ə-bŏlĭk) adj.
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