A forelock of a horse.
forelock definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
a lock of hair growing just above, or hanging over, the forehead
forelock definition by American Heritage Dictionary
A lock of hair that grows from or falls on the forehead, especially the part of a horse's mane that falls forward between the ears.
A cotter pin; a linchpin.