Definitions for "Foramen"
A small opening, perforation, or orifice; a fenestra.
a passage or opening; a communication between two cavities of an organ or a hole in a bone for passage of vessels or nerves
(L. aperture or hole): A communication between two cavities such as the brain ventricles or an opening in bone for passage of vessels and/or nerves.
A relatively large comma-shaped cavity (apical pore) on the Po plate of Alexandrium spp. (sometimes fishhook shaped as in Alexandrium catenella and A. tamarense). It is a diagnostic feature of the APC.