Wiktionary
trigonocephaly
n. A congenital condition of premature fusion of the metopic suture leading to a triangular-shaped forehead.
Wikipedia
Trigonocephaly
Trigonocephaly (Greek: 'trigonon' = triangle, 'kephale' = head) is a congenital condition of premature fusion of the metopic suture (Greek: 'metopon' = forehead) leading to a triangular shaped forehead. The merging of the two frontal bones leads to transverse growth restriction and parallel growth expansion. It may occur syndromic involving other abnormalities or isolated.