to ride down a hill using a longboard or skateboard as fast as possible

someone who is sexy beyond mean

verb. "Bombing hills" is the act of riding a downhill longboard down a hill. It can be used to mean any sort of riding, but specifically it means "to ride as fast as possible to the bottom."

used as a verb, "bombing hills" is the act of riding down a hill on a longboard (a downhill longboard, not a surfing longboard). You can do this in any number of ways (see longboard for examples), and no matter how you do it, it's pure fun.