The Latin term for a hole (plural, foramina). For example, the foramen magnum is the large opening in the base of the skull through which the brain and spinal cord are continuous. The foramen ovale is an aperture between the left and right ATRIUM of the fetal heart which should close at birth. It does not always do so, usually without consequences but rarely resulting in an unusual form of STROKE in which a blood clot from a vein breaks off, travels through the open foramen into the arterial circulation and is deposited in the brain. There may also be an association between patent foramen ovale and migraine