I. (ˈ)prē+ adjective
Etymology: pre- + frontal
: anterior to a frontal structure
a prefrontal bone
prefrontal convolution
a. : of or relating to a bone anterior and lateral to the frontal bone of some vertebrates
the prefrontal ectethmoid of a teleost fish
b. : of, relating to, or being a plate or scale in the center or on each side of the head of some reptiles and fishes in front of the frontal scale
c. : of, relating to, or constituting the anterior part of the frontal lobe of the brain bounded posteriorly by the ascending frontal convolution
II. noun
: a prefrontal part (as a scale or bone)