Theories abound as to the derivation of the pug's name. Because of his studly body, wrinkled head, and association with the Netherlands, the early pug was sometimes called the Dutch mastiff or the Dutch pug. He also went by the name dwarf mastiff, a reference to his small size. Some pug historians suggest that the breed took its name from the marmoset monkeys that were popular pets in the seventeenth and eighteenth centuries. The wrinkled marmosets were often referred to as pugs, and people may have taken to calling the wrinkle-faced dog a pug as well. A nineteenth-century dog writer named J. H. Walsh theorized that the breed name came from the Latin word pugnus, meaning “fist” — the shadow of a clenched fist was said to resemble the pug's profile. In the Netherlands and Germany, the pug's frowning expression gave rise to the nickname “mops” or mopshond, from the Dutch word meaning “to grumble.” That's not to say that the pug is pugnacious, however. He's a lover, not a fighter. In English-speaking countries today, the pug is affectionately nicknamed Puggy, Pugsley, Puggly, Puglet, and any number of similar derivations.