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acra·​nia (ˈ)ā-ˈkrā-nē-ə How to pronounce acrania (audio)
: congenital partial or total absence of the skull


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noun plural

in some classifications
: a division of the phylum or subkingdom Chordata comprising the hemichordates, tunicates, and lancelets and including all the chordates without true heads and anterior brains compare vertebrata

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Cite this Entry

“Acrania.” Medical Dictionary, Merriam-Webster, Accessed 17 Apr. 2024.

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