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

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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 To date, almost 25% of the sea lions that first responders bring to the Marine Mammal Center in Sausalito have died of this one aggressive cancer — among the highest prevalence of a single type of cancer in any mammal, including humans. Rosanna Xia, Star Tribune, "Sea lions are dying from a mysterious cancer. The culprits? Herpes and DDT," 11 Mar. 2021 Known to experts as PP-00128, the fragment of bone found in a southeastern Alaskan cave seemed to be from some large mammal that lived in the area thousands of years ago. Riley Black, Smithsonian Magazine, "Ancient DNA Reveals the Oldest Domesticated Dog in the Americas," 24 Feb. 2021 From estimates of as few as 300 there are now more than 350,000 and the animal is a symbol of America, appearing on seals and flags, even becoming the national mammal of the United States in 2016. Nat Newell, The Indianapolis Star, "'Happy to save a life': How Dale Earnhardt Jr. kept a buffalo from killing Conor Daly," 18 Mar. 2021 Created by a team led by embryologist Dr. Ian Wilmut, Dolly was the first mammal to be cloned from an adult cell. Matt Blitz, Popular Mechanics, "How to Clone Your Dog," 21 Dec. 2020 Those calves can also attract another great marine mammal: the orca, also known as the killer whale, which feeds on the young gray whales. oregonlive, "Spring whale watching will be another do-it-yourself event on the Oregon coast," 4 Mar. 2021 Now, the mammal itself is more scarce in its core range, and researchers are trying to figure out the best method to stabilize its population. Bob Timmons, Star Tribune, "Researchers deploy den boxes as possible tool to aid mysterious fishers," 4 Mar. 2021 Still, by 1958, neither mammal was on speaking terms with each other. David Fear, Rolling Stone, "‘Tom and Jerry’: Cat v. Mouse: Dawn of Justice," 26 Feb. 2021 Elizabeth Ann's birth evokes the landmark 1996 arrival of Dolly the Sheep, the first mammal to ever be cloned from the cells of an adult animal. Rob Picheta, CNN, "Meet Elizabeth Ann the ferret: The first endangered American animal to be cloned," 19 Feb. 2021

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.

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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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Statistics for mammal

Last Updated

8 Apr 2021

Cite this Entry

“Mammal.” Dictionary, Merriam-Webster, Accessed 13 Apr. 2021.

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More Definitions for mammal



English Language Learners Definition of mammal

: a type of animal that feeds milk to its young and that usually has hair or fur covering most of its skin


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

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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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