The Wetterhoun (FCI No.221, translated into English as the Frisian Water Dog) is a breed of dog traditionally used as a hunting dog for hunting small mammals and waterfowl in the province of Friesland in the Netherlands. The name of the dog comes from the West Frisian Wetterhûn meaning "water dog." Plural of Wetterhoun is Wetterhounen in Dutch. The breed may also be called the Otterhoun (not to be confused with the Otterhound) or Dutch Spaniel, although it is not a Spaniel-type dog.
The ancestral type of the Wetterhoun was developed at least 400 years ago in the Dutch province of Friesland. The origins of the Wetterhoun are conjectured to be from Gypsy dogs, crossed with an indigenous Frisian dog, perhaps the Old Water Dog, a type which is now extinct.Dogs of this type were kept for the difficult and dangerous hunting of fitch and otter in the water.The dogs were also used for retrieving waterfowl and as watch dogs. Although the dogs almost disappeared during World War II, fanciers were able to bring the breed back through careful breeding, and it is gaining in popularity.