a member of a group of ancient Greek philosophers who advocated the doctrine that virtue is the only good and that the essence of virtue is self-control
an intricate knot tied by Gordius, the king of Phrygia, and cut by the sword of Alexander the Great after he heard that whoever undid it would become ruler of Asia
any very difficult problem; insoluble in its own terms
armament consisting of a long cylindrical self-propelled underwater projectile that detonates on contact with a target
a small explosive device that is placed on a railroad track and fires when a train runs over it; the sound of the explosion warns the engineer of danger ahead
a small firework that consists of a percussion cap and some gravel wrapped in paper; explodes when thrown forcefully against a hard surface
an explosive device that is set off in an oil well (or a gas well) to start or to increase the flow of oil (or gas)