orthognathous (adj.)

in ethnology, "having the jaws not projecting beyond the vertical line of the forehead; straight-jawed," a characteristic of European skulls, 1853, from ortho- "straight, upright" + Greek gnathos "jaw, cheek," properly "the lower jaw," from PIE root *genu- (2) "jawbone, chin." Related: Orthognathic (by 1852); orthognathism.