inner cell mass

noun

in·​ner cell mass ˌin-ər- How to pronounce inner cell mass (audio)
: the portion of the blastocyst of a mammalian embryo that is destined to become the embryo proper

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Cite this Entry

“Inner cell mass.” Merriam-Webster.com Medical Dictionary, Merriam-Webster, https://www.merriam-webster.com/medical/inner%20cell%20mass. Accessed 1 May. 2025.

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