An aperture in an animal part or organ, especially one in a bone or cartilage. For example, the foramen magnum is the opening at the base of the skull through which the spinal cord passes.
Geology and Earth Sciences
A pore or opening. Applied to various openings, e.g. the pedicle foramen in Brachiopoda through which the pedicle emerges. In cephalopods (Cephalopoda) the term is applied to the opening in the septum through which the siphuncular cord passes.