出典:Wiktionary
出典:Wikipedia
出典:『Wikipedia』 (2011/07/26 19:14 UTC 版)
In anatomy, the foramen magnum (Latin: 'great hole') is a large opening in the occipital bone of the cranium. It is one of the several oval or circular apertures in the base of the skull (the foramina), through which the medulla oblongata (an extension of the spinal cord) enters and exits the skull vault.