A grotesque carved human or animal face or figure projecting from the gutter of a building, typically acting as a spout to carry water clear of a wall.
Typically, they were placed on the end of buttresses, pointing out from the buildings to project water away from the walls and foundations – protecting them from erosion.
Gargoyles were prevalent in medieval and Gothic architecture: mostly on churches and cathedrals. It’s thought that they were meant to frighten the largely illiterate population into coming to church.