The term 'Loop in a Lariat' is a reference to the knot known as a NOOSE, which is used to form a loop at the end of a lariat. A lariat is a type of rope used by cowboys to catch and tie up livestock. The NOOSE is a five-letter word, and is formed by tying a slip knot in the end of the rope. The knot is tightened by pulling on the free end of the rope, creating a loop that can be used to capture or restrain an animal.