has part has part has_part characteristic of part of has modifier abnormal supraoccipital bone morphology MP:0000078 MPheno.ontology The basioccipital, exoccipital and supraoccipital bones are distinct bones in prenatal, neonatal and some early juvenile stages in most mammals. In adult organisms, these structures are fused to form the unified adult occipital bone. any structural anomaly of the bone on the dorsal side of the great foramen of the skull, usually forming a part of the occipital in the adult, but distinct in the young supraoccipital bone dysplasia abnormal occipital bone morphology morphology abnormal supraoccipital bone