mammal

American  

[mam-uhl] / 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.

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mammal British  

/ ˈmæməl, mæˈmeɪlɪən /

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

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mammal Scientific  

/ măm′əl /

1. 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.

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Other Word Forms

• mammal-like adjective
• mammalian adjective
• mammallike adjective

Etymology

Origin of mammal

First recorded in 1820–30; as singular of New Latin Mammalia, neuter plural of Late Latin mammālis “of the breast”; equivalent to mamma ² + -al ¹

Compare meaning

How does mammal compare to similar and commonly confused words? Explore the most common comparisons:

• marsupial vs. mammal

Example Sentences

Fish such as wolf fish, peacock bass, and South American lungfish were especially common, accompanied by reptiles including caimans and turtles, and mammals such as capybaras, pacas, and armadillos.

From Science Daily

These enzymes operate similarly in all mammals, including humans, and their levels vary based on genetics, diet, and other biological factors.

From Science Daily

With more than 12,000 species, they outnumber birds and mammals.

From Science Daily

It has also lost more mammal species to extinction than any other continent.

From Barron's

The legislation, which made it illegal to hold certain marine mammals in captive, prevented the government from approving Marineland's China export plan.

From Barron's

Related Words

• beast
• creature
• vertebrate