Archaic anatomical term for the hipbone. In modern Japanese, 寛骨 (かんこつ) is the standard term.
In old medical books, the notation '無名骨' can be seen.
The term 無名骨 (lit. 'nameless bone') is a direct translation of the Latin 'os innominatum' (innominate bone), reflecting its historical anatomical designation. The exact derivation is uncertain, but it likely entered Japanese through early Western medical texts.