A widow's peak (also known as a widow's brow) is a descending V-shaped point in the middle of the hairline (above the forehead). It is an example of a dominant inherited trait. The term comes from English folklore, where it was believed that this hair formation was a sign of a woman who would outlive her husband.
The peak refers to the beak or bill of a headdress, particularly a widow's hood, making people think a woman was being given a mourning hood for her husband's forthcoming passing.
In popular culture, "evil" characters are often depicted with a widow's peak.
Source: newbielink:http://en.wikipedia.org/wiki/Widow's_peak [nonactive]