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Synonyms

mammalian

American  
[muh-mey-lee-uhn, -meyl-yuhn] / məˈmeɪ li ən, -ˈmeɪl jən /

noun

  1. an animal of the class Mammalia; mammal.


adjective

  1. belonging or pertaining to the class Mammalia; characteristic of mammals.

Other Word Forms

Etymology

Origin of mammalian

1825–35; < New Latin Mammali ( a ) ( see mammal) + -an

Explanation

Use the adjective mammalian to describe warm-blooded vertebrates with hair, or anything related to them. Your sister might be fond of snakes and frogs, while you'd prefer a mammalian pet, like a dog or cat. You, your pet dog, a gorilla, and a skunk all have something very important in common: you can all be described as mammalian, since you are all in the scientific class known as Mammalia. Mammalian characteristics range from having three small bones in each ear, to not being born inside an egg (with the exception of the platypus and other monotremes), to being nursed by a mother as an infant.

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Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

"There was so much prey available that mammalian predators couldn't have eaten it all," says Oscar Wilson, postdoctoral researcher at the University of Helsinki.

From Science Daily Aug. 19, 2026

Federal inspectors detailed multiple instances of mammalian hair found in drugs produced at a Catalent plant in Bloomington, Ind., used in part to manufacture semaglutide.

From MarketWatch Aug. 5, 2026

A smaller percentage also have sensitivity to dairy and have to avoid gelatin and products containing it—including Jell-O, gummy bears and even gelcap pain relievers—as well as medications made in mammalian cells.

From The Wall Street Journal Jun. 25, 2026

His current best theory is that it’s generated by quantum processes, suggesting that awareness exists on a continuous spectrum across all matter rather than remaining the exclusive domain of mammalian brains.

From Los Angeles Times Jun. 5, 2026

It creates a massive vapor lock, as it were, in mammalian fuel lines: The body is prevented from turning what it eats into a source of usable energy.

From "Into the Wild" by Jon Krakauer

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