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 Charles Darwin assumed that male mammals are usually bigger than their female counterparts. Will Sullivan, Smithsonian Magazine, 14 Mar. 2024 Hundreds of studies on young rats, monkeys, and humans show that young mammals want to play, need to play, and end up socially, cognitively, and emotionally impaired when they are deprived of play. Jonathan Haidt, The Atlantic, 13 Mar. 2024 Josh McInnes, a researcher at the University of British Columbia, told USA TODAY the incident shows that killer whales not only are competing with white sharks for seals in the waters off South Africa but also that the mammals can develop niche tastes and independently overpower white sharks. Christopher Cann, USA TODAY, 7 Mar. 2024 But mammals are not the only group of animals to feed their babies with specialized secretions. Popular Science, 7 Mar. 2024 The mammals typically live in shallow waters in the eastern North Pacific Ocean and hunt for food offshore on the coast, according to the National Oceanic and Atmospheric Association. Hanh Truong, Sacramento Bee, 29 Feb. 2024 The agency routinely samples wild birds, and only samples mammals in which there is suspicion. Susanne Rust, Los Angeles Times, 25 Feb. 2024 Board a boat that follows the coastline to the park, home to about 140 species of mammals, 116 reptiles and 400 birds. Jennifer Kester, Forbes, 23 Feb. 2024 On Sunday, the Virginia Aquarium & Marine Science Center Stranding Response Program, which coordinates responses for all marine mammals and sea turtles that come ashore in Virginia, arrived and pulled the whale up the beach to be monitored overnight, the aquarium confirmed to USA TODAY. USA TODAY, 4 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 29 Mar. 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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