* Hairline: This refers to the edge of the hair on the forehead.
* Fringe/Bangs: If the hair is cut short and falls over the forehead, it's often called a fringe or bangs (though "bangs" is more commonly used for women).
* Forelock: A lock of hair that grows or falls over the forehead.
* Front: Simply referring to the "front of the hair" is also common and understandable.
* Quiff: A hairstyle where the hair is brushed upwards and back from the forehead.
The best term to use depends on the specific hairstyle you're describing.