Source: The Collaborative International Dictionary of English v.0.48
blastocoel \blastocoel\, Blastocoele \Blas"to*c[oe]le\
blastocoele \blastocoele\, n. [Gr. blasto`s sprout + koi^los
hollow.] (Biol.)
The cavity inside a blastula; -- also called segmentationcavity.
[1913 Webster]