Toy dog traditionally refers to a very small dog or a grouping of small and very small breeds of dog. A toy dog may be of any of various dog types. Types of dogs referred to as toy dogs may include Spaniels, Pinschers and Terriers that have been bred down in size. Not all toy dogs are lapdogs, although that is an important and ancient type of toy dog. The very smallest toy dogs are sometimes called teacup size, although no major dog registry recognizes that term.
Small dogs 
Dogs referred to as toy dogs, and dogs found in the Toy Group of breed registries, may be of the very ancient lapdog type, or they may be small versions of hunting dogs or working dogs, bred down in size for a particular kind of work or to create a pet of convenient size. In the past, very small dogs not used for hunting were kept as symbols of affluence, as watchdogs, and for the health function of attracting fleas away from their owners.
Most major dog clubs in the English-speaking world have a Toy Group in which they place breeds of dog that the kennel club categorises as toy, based on size and tradition. The Kennel Club (UK), the Canadian Kennel Club, the American Kennel Club, the Australian National Kennel Council, and the New Zealand Kennel Club all have a Toy Group, all though they may not all categorise the same breeds as toy. The United States has a second major kennel club, the United Kennel Club, originally formed to offer a centralized stud book service for breeders of hunting dogs. Today the United Kennel Club registers all breeds and sponsors dog shows. It does not recognize a Toy Group. Small dogs are placed with larger dogs of their type, or in the Companion Dog Group. In 2008, the American Kennel Club begin investigating whether or not to change the name of the Toy Group to Companion Group in order to emphasise that dogs are not playthings, but the name change is resisted by traditionalists.
The Fédération Cynologique Internationale has established common nomenclature to ensure that pedigrees are mutually recognized in all 84 member countries. The following breed groupings (Sections) are recognized by the Fédération Cynologique Internationale in Group 9, Toy and Companion dogs.
- Section 1: Bichons and related breeds
- Section 2: Poodle
- Section 3: Small Belgian Dogs
- Section 4: Hairless Dogs
- Section 5: Tibetan breeds
- Section 6: Chihuahua
- Section 7: English Toy Spaniels
- Section 8: Japanese Chin and Pekingese
- Section 9: Continental Toy Spaniel
- Section 10: Kromfohrländer
- Section 11: Small Molossian type Dogs
Not including the colour and size varieties, breeds categorized by Fédération Cynologique Internationale members as Companion and Toy are listed here. Those with flags are also recognized by the non-member countries indicated by the flag.
- Bichon Havanais (Havanese)
- Bichon à poil frisé (Bichon Frise)
- Bolognese (Bolognese)
- Coton de Tuléar
- Petit chien lion (Löwchen, Little Lion Dog)
- Caniche (Poodle—all three sizes are in the Fédération Cynologique Internationale Companion and Toy Group)
- Griffon belge (Belgian Griffon)
- Griffon bruxellois (Brussels Griffon)
- Petit Brabançon (Small Brabant Griffon)
- Chinese Crested Dog
- Lhasa Apso
- Shih Tzu
- Tibetan Spaniel
- Tibetan Terrier
- Cavalier King Charles Spaniel
- King Charles Spaniel
- Japanese Chin (Chin)
- Epagneul nain Continental (Phalène, Continental Toy Spaniel)
- Bouledogue français (French Bulldog)
- Boston Terrier
- Russkiy Toy
- West Highland White Terrier
- French Bulldog
Registries within individual Fédération Cynologique Internationale members, such as the Australian National Kennel Council, may use a slightly different nomenclature, depending on the country. Non-member countries use other terminology, but the term Toy is only used to group dogs for show purposes.
In addition, these national organizations also recognize the following breeds in their Toy Group:
- Australian Silky Terrier
- Chihuahua (Long Coat)
- Chihuahua (Smooth Coat)
- Chihuahua (Short Coat)
- English Toy Terrier (Black and Tan)
- English Toy Spaniel
- Italian Greyhound
- Japanese Spaniel
- King Charles Spaniel
- Lowchen (Little Lion Dog)
- Manchester Terrier
- Miniature Pinscher
- Poodle (Toy)
- Silky Terrier
- Toy Fox Terrier
- Toy Manchester Terrier
- Yorkshire Terrier
The major national kennel club for each country will have its own list of breeds that it recognizes as Toy. In addition, some new or newly documented rare breeds may be awaiting approval by a given kennel club. Some new breeds may currently be recognized only by their breed clubs. Some rare new breeds have been given breed names, but may only be available from the breeder or breeders who are developing the breed, and may not yet be recognized by any kennel club.
In addition to the major registries, there are a nearly infinite number of sporting clubs, breed clubs, and internet-based breed registries and businesses in which dogs may be registered in whatever way the owner or seller wishes.
Teacup dogs 
The "Teacup" dog is not recognized by any major or reputable dog registries, thus it cannot be compared to a toy dog. The standard size for a toy dog ranges from 4 to 7 pounds; anything smaller than the standard size of a toy dog may be the runt of the litter.
Teacup dogs are popular today because of their interesting size at maturity; thus, they are commonly bred as they sell very quickly. However, as these dogs are prone to many health issues, there are risks for buyers who do not use reputable breeders that do genetic health testing and breed their dogs by the breed standard.
Most recognized breeders do not breed Teacups, as they do not breed anything smaller than 4 pounds.
"Teacup" dogs are often dogs that were born prematurely and carry greatly increased health risks. They are prone to heart failure, dental problems, behavioral/temperamental problems and various other complications, many of which are causes of their relatively short lifespans.
What makes a toy breed 
The diminutive Yorkshire Terrier is in the Toy Group of many breed registries. The Australian Terrier is one of the smallest terriers, but is usually listed in the Terrier group. In some registries, however, the Yorkshire Terrier is listed in the Companion Dog group. Some registries do not recognize a Toy category.
The use of the word "toy" to describe small dogs that belong to a toy breed is redundant and also incorrect, suggesting that the breed comes in different sizes—there is no such thing, for example, as a "toy Chihuahua"; all Chihuahuas are categorized in the Toy Group. Some breeds do come in different sizes, such as Poodles, which come in standard, miniature, and toy varieties. The size varieties may all be placed within one group, as with the German Spitz breed under the Fédération Cynologique Internationale rules, or the smallest varieties of a breed may be placed as a separate breed in the Toy Group or some other group. The exact categorization varies between registries and countries. The pug is probably the largest of the toy dog group, weighing an average of up to 18 pounds.
The very smallest toy dogs are sometimes called "teacup" size, although no major dog registry recognizes that term. Most dogs labeled "teacup" dogs are simply undersized dogs (usually runts). The name is often applied to small dogs by unscrupulous breeders in order to make more money off of the dog by making it seem special. Dogs bred to be "teacups" often have many health problems associated with them.
The Shih Tzu is a toy dog; however, some refer to the Shih Tzu as teacup, toy, toi, pint-size, pocket, imperial, IMP, Chinese imperial dog, CID, mini, miniature or standard. All these references are considered inappropriate and are categorically rejected by the American Shih Tzu Club, Inc. as the National Breed Club maintains there is but one “Shih Tzu” and the ideal weight is 9-16 lbs. (This does not negate the fact that size may vary and those smaller than what is defined as the ideal are not uncommon in litters produced by sires and dams that fall within the ideal weight range.) The use of such descriptive labels is generally regarded as a misleading marketing ploy, as is pitching Shih Tzu to be of "rare color."
Form versus function 
Another area of contention is the idea that toy dogs are only companion animals, slow moving, with little need for exercise and with low endurance. Papillons give lie to this; although dainty and small they are quite capable of taking long walks with their owners and often excel at the energetic sport of dog agility. Maltese are another example of very robust daintiness. The United Kennel Club (US), which does not recognize a Toy group, defines Italian Greyhounds as having been bred exclusively as pets; the American Kennel Club states that these dogs were bred as gazehounds, dogs that hunt by sight, and are quite fast and hardy, but they are nevertheless placed in the Toy group.
See also 
- Bruce Felton and Mark Fowler (1994). "Fashion and Grooming". The Best, Worst, and Most Unusual. New York: Galahad Books. p. 538. ISBN 0-88365-861-5.
- United Kennel Club (US) breed groups
- Toys Are Us? by Stephanie Abraham, AKC Gazette, September 2008, pp 55-56
- Fédération Cynologique Internationale Group 9
- The Kennel Club Toy Group
- Australian National Kennel Council
- New Zealand Kennel Club breed groups
- Canadian Kennel Club Group 5
- American Kennel Club Toy Group
- Dog Breed Registries in North America
- "Shih Tzu: A Toy Dog". Retrieved 2011-07-23.
- Toy Group at the Open Directory Project
- Toy Dog Breeds That Don't Shed
- Types of Small Dogs at Dogalicious.net