mammal

[mam-uhl]

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.

mammal

/ 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

mammal

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.

Other Word Forms

• mammal-like adjective
• mammalian adjective
• mammallike adjective

Word History and Origins

Origin of mammal¹

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

Word History and Origins

Origin of mammal¹

C19: via New Latin from Latin mamma breast

Example Sentences

Patients who found it difficult to talk about their problems in the office opened up once they got in the water with these empathetic mammals.

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Overwhelmed by these exotic sights, this visitor completely overlooked the presence of small, shrew-like mammals—the very creatures whose descendants would, eventually, inherit the earth.

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That made them vulnerable to the mammals that arrived with European settlers in the 19th century.

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The next day, the agency took down the photo and said that no mammal parts had been taken from the beach after all.

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They had previously been characterized as entirely herbivorous, like gorillas, Goodall observed them hunting, killing and eating small mammals such as bush pigs and colobus monkeys, by any standard a complicated collaborative enterprise.

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Related Words

• beast 
• creature 
• vertebrate