A unibrow (or jacco brow or monobrow; called synophrys in medicine) is a single eyebrow created when the two eyebrows meet in the middle above the bridge of the nose. The hair above the bridge of the nose is of the same color and thickness as the eyebrows, such that they converge to form one uninterrupted line of hair.

Reference
Wiki: Congenital muscular hypertrophy-cerebral syndrome