endocoelar
/ˌɛndəˈsɛljər, -sɪˈlɑr/Definitions
1. adjective
relating to or forming part of the inner layer of cells in an embryo, especially in a chordate.
“The endocoelar cells are crucial for the development of the organism.”
2. noun
an endocoelar cell or tissue.
“The endocoelar cells play a vital role in the formation of the notochord.”