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acephaly a·ceph·a·ly (ā-sěf'ə-lē, ə-sěf'-) or a·ce·pha·li·a (ā'sə-fā'lē-ə, ās'ə-) or a·ceph·a·lism (ā-sěf'ə-lĭz'əm, ə-sěf'-)n. Congenital absence of the head.
Such a monstrosity is known as acephaly in modern nomenclature.