prefrontal adj 1: anterior to a frontal structure; "a prefrontal bone"; "prefrontal lobes"
Prefrontal \Pre*fron"tal\, a. (Anat. & Zool.) Situated in front of the frontal bone, or the frontal region of the skull; ectethmoid, as a certain bone in the nasal capsule of many animals, and certain scales of reptiles and fishes. -- n. A prefrontal bone or scale. [1913 Webster]