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 mammalian (audio) , ma-​ \ adjective or noun
mammal-like \ ˈma-​məl-​ˌlīk How to pronounce mammal-like (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

Learn about the hundreds of species of birds, reptiles, and mammals that inhabit this thriving ecosystem while exploring the winding trails of the refuge. National Geographic, "Wild Costa Rica Escape: Guanacaste’s Coral Reefs and Volcanic Peaks," 17 June 2019 Delegates heard that Angola’s Okavango Delta area is some of the world’s most important remaining wilderness, and the country has the potential to host one of the most diverse mammal populations on the continent., "Prince Harry Follows in Mom Princess Diana's Footsteps by Advocating for Clearing Landmines," 17 June 2019 Any wild mammal including raccoons, skunks, foxes and coyotes can have rabies and infect humans, the health department said. Kirk Mitchell, The Denver Post, "Rabid bat found near Belmar spurs public health warning from Jefferson County," 17 June 2019 At least 90% of all whales hit by large vessels die, and most of those sink, said Calambokidis, whose four-decade career as a marine-mammal researcher includes study of ship impacts. Mike Lindblom, The Seattle Times, "Whale-ferry collision in Seattle’s Elliott Bay a byproduct of humpback revival, and could become more common," 30 May 2019 Norwegian scientists were convinced: The beluga whale stalking boats off the Arctic coast was an operative from the Russian base in Murmansk that trains sea mammals for military missions. ... Thomas Grove, WSJ, "Is That Whale a Russian Agent? The Beluga Won’t Tell," 11 May 2019 For example, fetal mammals have a special hemoglobin in their blood with extra affinity for oxygen, which helps them to draw oxygen out of the maternal blood supply in the placenta. Quanta Magazine, "Icefish Study Adds Another Color to the Story of Blood," 22 Apr. 2019 Wild small mammals in Paraguay do not naturally engage in wheel running. Rafil Kroll-zaidi, Harper's magazine, "Findings," 10 Jan. 2019 The commission's website lists licensed wildlife rehabilitators who can be contacted for small mammals, birds, amphibians and reptiles. Cassie Cope, charlotteobserver, "A young doe became trapped in a stormwater drain. There's a happy ending. | Charlotte Observer," 19 May 2018

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

1813, 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

23 Jun 2019

Look-up Popularity

Time Traveler for mammal

The first known use of mammal was in 1813

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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 mammalian (audio) \ adjective or noun

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More from Merriam-Webster on mammal

Spanish Central: Translation of mammal

Nglish: Translation of mammal for Spanish Speakers

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

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