In common usage, a scoop is any specialized spoon used to serve food.
In the technical terms used by the food service industry and in the retail and wholsale food utensil industries, there is a clear distinction between two types of scoop: the disher, which is used to serve ice cream, measure a portion e.g. cookie dough, or to make melon balls; and the scoop which is used to measure or to transfer an unspecified amount of a bulk dry foodstuff such as rice, flour, or sugar.
Dishers are usually hemispherical like an ice cream scoop, while measuring scoops are usually cylindrical, and transfer scoops are usually shovel-shaped.
Some dishers have mechanical devices which help get the contents out of the scoop. Some ice cream scoops are liquid-filled to keep the ice cream from freezing to the scoop's metal. Traditionally dishers are sized by the number of scoops per quart but may also be sized by ounces, the diameter of the bowl, or the number of tablespoons they hold.