A ruse is a clever trick or deception designed to fool someone. When a magician makes you watch one hand while secretly doing something with the other, that misdirection is a ruse. When a character in a story pretends to be sick to avoid going somewhere, they're using a ruse.

The word suggests more than a simple lie. A ruse usually involves some planning and creativity. In the classic game Stratego, you might place weak pieces at the front as a ruse, making your opponent think you're poorly defended while your strong pieces wait in ambush. In The Great Brain books, Tom Fitzgerald often devises elaborate ruses to trick other kids or get out of trouble.

Ruses appear frequently in stories of espionage and warfare. During World War II, the Allies created an entire fake army with inflatable tanks and dummy radio transmissions to convince the Germans they would invade at Calais rather than Normandy. This massive ruse helped ensure the success of D-Day.