Apotropaic magic or protective magic is a type of magic intended to turn away harm or evil influences, as in deflecting misfortune or averting the evil eye. Apotropaic observances may also be practiced out of superstition or out of tradition, as in good luck charms, amulets, or gestures such as crossed fingers or knocking on wood. Many different objects and charms were used for protection throughout history.

In architecture, and specifically Gothic architecture, a gargoyle is a carved or formed grotesque with a spout designed to convey water from a roof and away from the side of a building, thereby preventing it from running down masonry walls and eroding the mortar between. Architects often used multiple gargoyles on a building to divide the flow of rainwater off the roof to minimize potential damage from rainstorms. A trough is cut in the back of the gargoyle and rainwater typically exits through the open mouth. Gargoyles are usually elongated fantastical animals because their length determines how far water is directed from the wall. When Gothic flying buttresses were used, aqueducts were sometimes cut into the buttress to divert water over the aisle walls.