Foramen \Fo*ra"men\, n.; pl. L. Foramina, E. Foramines. [L., fr. forare to bore, pierce.]

A small opening, perforation, or orifice; a fenestra.

Foramen of Monro (Anat.), the opening from each lateral into the third ventricle of the brain.

Foramen of Winslow (Anat.), the opening connecting the sac of the omentum with the general cavity of the peritoneum.

Source: Webster's Revised Unabridged Dictionary (1913)