The word "embryonic" refers to something that is in an early stage of development, like how a baby grows inside its mother before being born. Full definition
The morality of human embryonic stem cell research has long been contentious, but new discoveries could end the controversy. (psmag.com)
Federal officials have approved the start of human embryonic stem cell treatment experiments on patients suffering a leading cause of vision loss. (robertlanza.com)
Thus, they consider the use of embryonic stem cells for research purposes as unconstitutional. (sciencemag.org)