Main Entry: em·bryo

Pronunciation: \ˈem-brē-ˌō\

Function: noun

Inflected Form(s): plural em·bry·os

Etymology: Medieval Latin embryon-, embryo, from Greek embryon, from en- + bryein to swell; akin to Greek bryon catkin

Date: 1548

1 a archaic : a vertebrate at any stage of development prior to birth or hatching b : 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
2 : the young sporophyte of a seed plant usually comprising a rudimentary plant with plumule, radicle, and cotyledons
3 a : something as yet undeveloped b : a beginning or undeveloped state of something <productions seen in embryo during their out-of-town tryout period — Henry Hewes>