The bone forming the forehead and roof of the eye orbit.
Comment:
[development-note] "In the mouse the parietal originates from cephalic paraxial mesoderm (Jiang 2000; Morriss-Kay 2001), whereas in the chicken it is traced back to either mesodermal (Noden 1978) or neural crest (Couly 1992, 1993)."; [taxon-note] "fused in humans, paired in other animals"