Mammals

[mam-uh l] /ˈmæm əl/

noun
1.
any vertebrate of the class Mammalia, having the body more or less covered with hair, nourishing the young with milk from the mammary glands, and, with the exception of the egg-laying monotremes, giving birth to live young.
/ˈmæməl/
noun
1.
any animal of the Mammalia, a large class of warm-blooded vertebrates having mammary glands in the female, a thoracic diaphragm, and a four-chambered heart. The class includes the whales, carnivores, rodents, bats, primates, etc
n.

1826, anglicized form of Modern Latin Mammalia (1773), coined 1758 by Linnaeus for the class of mammals, from neuter plural of Late Latin mammalis “of the breast,” from Latin mamma “breast,” perhaps cognate with mamma.
mammal
(mām’əl)
Any of various warm-blooded vertebrate animals of the class Mammalia, whose young feed on milk that is produced by the mother’s mammary glands. Unlike other vertebrates, mammals have a diaphragm that separates the heart and lungs from the other internal organs, red blood cells that lack a nucleus, and usually hair or fur. All mammals but the monotremes bear live young. Mammals include rodents, cats, dogs, ungulates, cetaceans, and apes.

A class of vertebrates characterized by the production of milk by the females and in most cases, by a hairy body covering. Most mammals give live birth to their young. Human beings are mammals.