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

The researchers point to earlier work on beaked whale circovirus that suggested a link to immunosuppression, a pattern that aligns with how circoviruses affect some land mammals and birds.

From Science Daily

The coastal city was also the site of a massive oil spill in 1969 that killed thousands of birds, fish and sea mammals, and helped launch the state’s environmental movement.

From Los Angeles Times

Mountain lions have the widest geographic range of any native mammal in the Americas apart from humans, stretching from western Canada to Argentina.

From Barron's

Since then, the site has produced fossils of turtles, lizards, and mammals, along with many snake remains, including some that have played an important role in paleontology.

From Science Daily

Icebergs colliding and the chatter of marine mammals generate sounds that complicate submarine detection.

From The Wall Street Journal

Related Words

• beast
• creature
• vertebrate