mammal

noun

mam·​mal ˈma-məl How to pronounce mammal (audio)
: 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
mammalian adjective or noun
mammal-like adjective
or less commonly mammallike
mammal-like behavior
mammallike reptiles

Examples of mammal in a Sentence

Human beings, dogs, and cats are all mammals.
Recent Examples on the Web The virus has caused large outbreaks in mink and foxes, and wiped out thousands of marine mammals, especially in South America. Apoorva Mandavilli, New York Times, 9 Apr. 2024 The voracious Burmese python has done widespread damage to the Everglades food chain, pretty much wiping out populations of small mammals like marsh bunnies and gulping down everything from birds to alligators. Ashley Miznazi, Miami Herald, 8 Apr. 2024 The early evolution of mammals is a little bit murky, with some placental mammals even likely living alongside dinosaurs and others arising much later. Laura Baisas, Popular Science, 4 Apr. 2024 There have been large die offs of marine mammals in South America and a particularly alarming outbreak on a mink farm in Spain. Will Stone, NPR, 4 Apr. 2024 Since avian flu spilled over into mammals, its potential to evolve and infect humans has remained a concerning unknown for scientists. Christian Thorsberg, Smithsonian Magazine, 2 Apr. 2024 Although the research was performed in mice, certain brain processes have remained almost the same as mammals have evolved, so the findings can tell us a lot about ourselves, said the study’s senior author, Dr. György Buzsáki, Biggs Professor of Neuroscience at NYU Langone Health. Linda Carroll, NBC News, 29 Mar. 2024 It is also specially designed to provide a habitat for birds and mammals that mimics the thermal performance of natural log hollows. Jon Stojan, USA TODAY, 27 Mar. 2024 Two species of rhinos are contenders for the title of rarest land mammal for different reasons. Clare Mulroy, USA TODAY, 29 Mar. 2024

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'mammal.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

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 entry 1

First Known Use

1811, in the meaning defined above

Time Traveler
The first known use of mammal was in 1811

Dictionary Entries Near mammal

Cite this Entry

“Mammal.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/mammal. Accessed 16 Apr. 2024.

Kids Definition

mammal

noun
mam·​mal ˈmam-əl How to pronounce mammal (audio)
: any of a class of warm-blooded vertebrates that include human beings and all other animals that nourish their young with milk produced by mammary glands and have the skin usually more or less covered with hair

Medical Definition

mammal

noun
mam·​mal ˈmam-əl How to pronounce mammal (audio)
: any of the higher vertebrate animals comprising the class Mammalia
mammalian adjective or noun

More from Merriam-Webster on mammal

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