Measles: An acute, contagious viral disease, usually occurring in childhood and characterized by eruption of red spots on the skin, fever, and catarrhal symptoms. Also called rubeola.

Measure Out: Measured height at withers was determined to be outside the limits for that breed as set forth in the breed standard.

Medial: Toward the mid line of the dog.

Median Line: See Furrow

Merle: A marking pattern, used in conjunction with another color, to describe Shetland Sheepdogs, Collies, Great Danes, and Australian Shepherds. The color is characterized by a marbling effect of dark patches against a lighter background of the same color. Color definitions may vary by breed. Always check the breed standard for the definitive color description.

Metatarsus: The corresponding part of the hind foot in quadrupeds or of the foot in birds.

Microchip: A rice-sized device encoded with a unique and unalterable number. The chip is implanted just under the skin in the scruff of the neck and is read by a scanner.

Milk Teeth: The first, temporary teeth. Also called baby teeth.

Miniature Pinscher: A breed of small dogs resembling the Doberman pinscher but typically reaching a height of only 25-30 centimeters (10-12 inches).

Miscellaneous Class: Transitory class for breeds attempting to advance to full recognition by a breed association.

Mismark: (1) Coat or color. (2) A dog that has coat coloration or markings not conforming to that which is acceptable for the breed.

Mites: Any of various small or minute arachnids of the order Acarina that are often parasitic on animals and plants, infest stored food products, and in some species transmit disease.