blas·​to·​mere ˈbla-stə-ˌmir How to pronounce blastomere (audio)
: one of the cells that are produced during cleavage of a zygote and that form the morula

Example Sentences

Recent Examples on the Web First, the isolated cell can be co-cultured with blastomeres from other embryos biopsied during the IVF cycle (there are almost always multiple embryos undergoing PGD biopsy per cycle). Wired Blogs, WIRED, 21 Sep. 2006

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'blastomere.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


blasto- + -mere

First Known Use

1875, in the meaning defined above

Time Traveler
The first known use of blastomere was in 1875

Dictionary Entries Near blastomere

Cite this Entry

“Blastomere.” Dictionary, Merriam-Webster, Accessed 30 Mar. 2023.

Medical Definition


blas·​to·​mere ˈblas-tə-ˌmi(ə)r How to pronounce blastomere (audio)
: a cell produced during cleavage of a fertilized egg

called also cleavage cell

blastomeric adjective

More from Merriam-Webster on blastomere

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