part of part of develops from develops from derived from ancestral fusion of derived from ancestral fusion of Homo sapiens caudal vertebra bony pelvis coccyx http://upload.wikimedia.org/wikipedia/commons/9/91/Gray100.png https://cdn.humanatlas.io/digital-objects/ref-organ/pelvis-female/v1.3/assets/3d-vh-f-pelvis.glb https://cdn.humanatlas.io/digital-objects/ref-organ/pelvis-male/v1.3/assets/3d-vh-m-pelvis.glb coccygeal Small, bony element consisting of several fused, rudimentary caudal vertebrae; near metamorphosis the hypochord fuses to the coccyx, thereby forming the urostyle.[AAO] coccygeal skeleton EHDAA2:0000259 coccyx [vertebrae coccygeae I-IV] fused caudal vertebral column os coccygis UBERON:0001350 coccygeal vertebrae I-IV FMA:20229 AAO:0000731 SCTID:182028002 coccyx [coccygeal vertebrae I-IV] os coccygis MESH:D003050 Wikipedia:Coccyx In humans: The coccyx, commonly referred to as the tailbone, is the final segment of the human vertebral column. Comprising three to five separate or fused vertebrae (the coccygeal vertebrae) below the sacrum, it is attached to the sacrum by a fibrocartilaginous joint, the sacrococcygeal symphysis, which permits limited movement between the sacrum and the coccyx. UMLS:C0009194 NCIT:C12696 GAID:239 tailbone A collection of caudal vertebrae in the coccygeal region that are fused and part of the bony pelvis. galen:Coccyx fused caudal vertebrae bone of dorsum caudal region of vertebral column embryonic post-anal tail irregular bone