Word Study
blastula
CIDE DICTIONARY
blastula, n. [NL., dim. of Gr. blasto`s a sprout.].
That stage in the development of the ovum in which the outer cells of the morula become more defined and form the blastoderm. [1913 Webster]
OXFORD DICTIONARY
blastula, n. (pl. blastulae or US blastulas) Biol. an animal embryo at an early stage of development when it is a hollow ball of cells.
Etymology
mod.L f. Gk blastos sprout
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