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Medical Dictionary

embryo

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noun em·bryo \ˈem-brē-ˌō\

Medical Definition of embryo

plural embryos

  1. 1archaic :  a vertebrate at any stage of development prior to birth or hatching

  2. 2:  an animal in the early stages of growth and differentiation that are characterized by cleavage, the laying down of fundamental tissues, and the formation of primitive organs and organ systems; especially :  the developing human individual from the time of implantation to the end of the eighth week after conception—compare fetus





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