mam·​mal | \ ˈma-məl How to pronounce mammal (audio) \

Definition of mammal

: any of a class (Mammalia) of warm-blooded higher vertebrates (such as placentals, marsupials, or monotremes) that nourish their young with milk secreted by mammary glands, have the skin usually more or less covered with hair, and include humans

Other Words from mammal

mammalian \ mə-​ˈmā-​lē-​ən How to pronounce mammal (audio) , ma-​ \ adjective or noun
mammal-like \ ˈma-​məl-​ˌlīk How to pronounce mammal (audio) \ or less commonly mammallike adjective
mammal-like behavior mammallike reptiles

Examples of mammal in a Sentence

Human beings, dogs, and cats are all mammals.
Recent Examples on the Web Before the discovery about the Brasilodon's age, scientists had previously confirmed that the Morganucodon, another small, rodent-like creature, was the world's earliest mammal. Wyatte Grantham-philips, USA TODAY, 8 Sep. 2022 This mammal is covered in scales and yet on the brink of global extinction. Nyeema C. Harris, Scientific American, 17 June 2022 Native to central Texas, this ancient mammal in a reptilian body is often found as roadkill along the highway. Steve Ditlea, SPIN, 14 Mar. 2022 The 13-foot white mammal was successfully lifted out of the river, where its surprising presence had drawn international attention and mounting concerns for its health. Elizabeth Kuhr, NBC News, 10 Aug. 2022 Dolly was the first mammal to be successfully cloned from an adult somatic cell, which is any type of bodily cell that is not a reproductive germ cell. Bill Frist, Forbes, 2 Aug. 2022 Pangolins are believed to be the most trafficked mammal in the world, per the WWF. Sarah Kuta, Smithsonian Magazine, 20 July 2022 The slowest mammal in the world is the three-toed sloth. Anna Kaufman, USA TODAY, 6 Aug. 2022 The autopsy confirmed that the dead marine mammal was male and 4 years old. Katie Hunt, CNN, 15 July 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'mammal.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of mammal

1811, in the meaning defined above

History and Etymology for mammal

from base of New Latin Mammalia (Linnaeus), class name, noun derivative from neuter plural of mammālis, from Latin mamma "breast, udder" + -ālis -al entry 1 — more at mamma

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Dictionary Entries Near mammal

mamma's boy



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Last Updated

23 Sep 2022

Cite this Entry

“Mammal.” Dictionary, Merriam-Webster, Accessed 24 Sep. 2022.

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More Definitions for mammal


mam·​mal | \ ˈma-məl How to pronounce mammal (audio) \

Kids Definition of mammal

: a warm-blooded animal (as a dog, mouse, bear, whale, or human being) with a backbone that feeds its young with milk produced by the mother and has skin usually more or less covered with hair


mam·​mal | \ ˈmam-əl How to pronounce mammal (audio) \

Medical Definition of mammal

: any of the higher vertebrate animals comprising the class Mammalia

Other Words from mammal

mammalian \ mə-​ˈmā-​lē-​ən, ma-​ How to pronounce mammal (audio) \ adjective or noun

More from Merriam-Webster on mammal

Nglish: Translation of mammal for Spanish Speakers

Britannica English: Translation of mammal for Arabic Speakers Encyclopedia article about mammal

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