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Synonyms

mammalian

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

noun

  1. an animal of the class Mammalia; mammal.


adjective

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

Other Word Forms

  • mammality noun
  • nonmammalian noun
  • unmammalian adjective

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.

Modern analytic tools, in particular methods introduced in 2009 to sequence the genetic material of individual mammalian cells, have revealed how pervasive these changes are.

From The Wall Street Journal • Apr. 20, 2026

The focus of the convention on mammalian species over others like fish and insects has previously been a criticism of the agreement.

From BBC • Mar. 24, 2026

Perceptive viewers may have noticed a mammalian bias in the original — there were no reptiles to be found in its near-perfect society.

From Los Angeles Times • Dec. 23, 2025

"More specifically, if they have unexpected episodes of severe abdominal pain occurring several hours after eating mammalian meat, they should be investigated for possible sensitization to the oligosaccharide alpha-gal."

From Science Daily • Dec. 17, 2025

Eurasian peoples happened to inherit many more species of domesticable large wild mammalian herbivores than did peoples of the other continents.

From "Guns, Germs, and Steel: The Fates of Human Societies" by Jared M. Diamond