What does the term duck call refer to?

A duck call is a device used to imitate the sound of a duck, typically for the purpose of attracting ducks during hunting. Duck calls are typically made of wood, acrylic, or metal, and come in a variety of shapes and sizes. They are blown into by the user, who produces sound by vibrating their lips against a reed. The sound produced by a duck call can vary depending on the design of the call and the technique of the user, and can be used to imitate the calls of different species of ducks. Duck calls are often used by waterfowl hunters to attract ducks within range of their guns.