any vertebrate of the class Mammalia, having the body more or less covered with hair, nourishing the young with milk from the mammary glands, and, with the exception of the egg-laying monotremes, giving birth to live young.
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- mam·mal·like, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
How to use mammal in a sentence
Dellaire told me that while no marine mammals have been found yet infected with SARS-CoV-2, “…beluga whales and dolphins have been found to be infected by related gammacoronaviruses.”Everything we know—and don’t know—about human-to-animal COVID transmission | jakemeth | September 4, 2020 | Fortune
In some intriguing cases, that loss of genes isn’t known to cause disease symptoms in any other mammals.By Losing Genes, Life Often Evolved More Complexity | Viviane Callier | September 1, 2020 | Quanta Magazine
With 45 species of mammals and more than 200 species of birds from six continents, the refuge is more biodiverse than almost any area in the Arctic.The Trump administration opened the Arctic National Wildlife Refuge to oil companies—but none may bite | By Scott L. Montgomery/The Conversation | August 26, 2020 | Popular-Science
A yellow-rumped leaf-eared mouse has shattered the world record as the highest-dwelling mammal yet documented.A South American mouse is the world’s highest-dwelling mammal | Jack J. Lee | July 29, 2020 | Science News
Many sleep discoveries first made in flies have been verified in mammals.
The term “gestation,” for instance, is derived from the Latin verb gestāre, used to describe a mammal carrying a burden.
A flea, Xenopsylla cheopis, from an infected little mammal—usually a rat—can hop from the dying rat onto a human and bite it.It’s Not Time to Worry About China’s Plague Just Yet | Kent Sepkowitz | July 23, 2014 | THE DAILY BEAST
Fernandez-Duque discovered that owl monkeys are the only reliably monogamous mammal species.P.J. on the Owl-Monkey Project and the Science of Chick Flicks | P. J. O’Rourke | April 6, 2014 | THE DAILY BEAST
If you like mammal species from the suborder Vermilingua (meaning "worm tongue")...The March Madness Teams to Cheer If Yours Got Bounced | Ben Teitelbaum | March 16, 2014 | THE DAILY BEAST
Nicaragua: Nicaragua boasts not one, but two species of everyone's favorite armored mammal, the armadillo.
No insect—so far as I can remember—has a thick neck; nor has any mammal or bird a thin one, like the wasp, bee, or fly.Ancient Faiths And Modern | Thomas Inman
Without it a mammal will perish in less than three minutes; hence there is no need of the body so urgent as that of oxygen.Voice Production in Singing and Speaking | Wesley Mills
The bat's secret appears to be that he is not the bird-mammal, but the mammal-insect: economy of tissue, hibernation.The Natural Philosophy of Love | Remy de Gourmont
Once more the ever-hungry little mammal claimed the spoils of victory.Wild Folk | Samuel Scoville
Then Quawteaht a second time gave strength and down the mammal plunged dragging with him the second Thunder Bird.Indian Legends of Vancouver Island | Alfred Carmichael
British Dictionary definitions for mammal
any animal of the Mammalia, a large class of warm-blooded vertebrates having mammary glands in the female, a thoracic diaphragm, and a four-chambered heart. The class includes the whales, carnivores, rodents, bats, primates, etc
- mammalian (mæˈmeɪlɪən), adjective, noun
- mammal-like, adjective
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Scientific definitions for mammal
Any of various warm-blooded vertebrate animals of the class Mammalia, whose young feed on milk that is produced by the mother's mammary glands. Unlike other vertebrates, mammals have a diaphragm that separates the heart and lungs from the other internal organs, red blood cells that lack a nucleus, and usually hair or fur. All mammals but the monotremes bear live young. Mammals include rodents, cats, dogs, ungulates, cetaceans, and apes.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.