: 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
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
Third, prolonged circulation in cattle increases the risk of the virus adapting to mammals, including humans.
—
Kimberly Dodd, The Conversation, 16 Jan. 2025
Péron recorded 23 species of mammals on the peninsula, but by 1990, with stock-keeping degrading the land and introduced predators such as foxes and feral cats taking their toll on the local wildlife, fewer than half that number remained.
—Keith Drew, AFAR Media, 16 Jan. 2025
The story white scientists crafted about these first mammals showed how deep time could operate to exclude.
—Caroline Winterer / Made By History, TIME, 14 Jan. 2025
Taken together with the bones, however—and with some help from modern technology—these earthen imprints give a holistic picture of the prehistoric creatures that sashayed along in their heyday, oblivious to the puny mammals of the future who would gawk at their footprints millions of years later.
—Shi En Kim, Smithsonian Magazine, 7 Jan. 2025
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Kimberly Dodd, The Conversation, 16 Jan. 2025
Péron recorded 23 species of mammals on the peninsula, but by 1990, with stock-keeping degrading the land and introduced predators such as foxes and feral cats taking their toll on the local wildlife, fewer than half that number remained.
—Keith Drew, AFAR Media, 16 Jan. 2025
The story white scientists crafted about these first mammals showed how deep time could operate to exclude.
—Caroline Winterer / Made By History, TIME, 14 Jan. 2025
Taken together with the bones, however—and with some help from modern technology—these earthen imprints give a holistic picture of the prehistoric creatures that sashayed along in their heyday, oblivious to the puny mammals of the future who would gawk at their footprints millions of years later.
—Shi En Kim, Smithsonian Magazine, 7 Jan. 2025
See all Example Sentences for mammal
Dictionary Entries Near mammal
Cite this Entry
“Mammal.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/mammal. Accessed 22 Jan. 2025.
Copy CitationKids Definition
mammal
noun
mam·mal
ˈmam-əl 
: 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
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