orbital fissure

noun

: either of two openings transmitting nerves and blood vessels to or from the orbit:

a

: one situated superiorly between the greater wing and the lesser wing of the sphenoid bone

called also superior orbital fissure, supraorbital fissure

b

: one situated inferiorly between the greater wing of the sphenoid bone and the maxilla

called also inferior orbital fissure, infraorbital fissure, sphenomaxillary fissure