What do you have in common with your hamster, a whale, a bat, a giraffe, and the kid who packs your groceries? Every one is a mammal — a hairy, warm-blooded, milk-drinking vertebrate, just like you.

All mammals are part of the scientific class mammalian, which got its name from the mammary glands used to nourish mammal babies. A note of interest: although a characteristic of mammals is that babies are born live, there’s a group of mammals called monotremes, like the platypus, that lay eggs; but whose young’uns, after they hatch, still get fed mama’s milk. Go figure.

Definitions of mammal

n any warm-blooded vertebrate having the skin more or less covered with hair; young are born alive except for the small subclass of monotremes and nourished with milk

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incomplete skeleton of female found in eastern Ethiopia in 1974
Sir Barton
thoroughbred that won the triple crown in 1919
Gallant Fox
thoroughbred that won the triple crown in 1930
thoroughbred that won the triple crown in 1935
War Admiral
thoroughbred that won the triple crown in 1937
thoroughbred that won the triple crown in 1941
Count Fleet
thoroughbred that won the triple crown in 1943
thoroughbred that won the triple crown in 1946
thoroughbred that won the triple crown in 1948
thoroughbred that won the triple crown in 1973
Seattle Slew
thoroughbred that won the triple crown in 1977
thoroughbred that won the triple crown in 1978
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female mammal
animals that nourish their young with milk
any mammal with prominent tusks (especially an elephant or wild boar)
primitive oviparous mammals found only in Australia and Tasmania and New Guinea
primitive pouched mammals found mainly in Australia and the Americas
eutherian, eutherian mammal, placental, placental mammal
mammals having a placenta; all mammals except monotremes and marsupials
fossorial mammal
a burrowing mammal having limbs adapted for digging
egg-laying mammal, monotreme
the most primitive mammals comprising the only extant members of the subclass Prototheria
marsupial, pouched mammal
mammals of which the females have a pouch (the marsupium) containing the teats where the young are fed and carried
farm animal, livestock, stock
any animals kept for use or profit
mature male of various mammals of which the female is called `cow'; e.g. whales or elephants or especially cattle
mature female of mammals of which the male is called `bull'
an animal in its second year
mature male of various mammals (especially deer or antelope)
mature female of mammals of which the male is called `buck'
small insect-eating mainly nocturnal terrestrial or fossorial mammals
aquatic mammal
whales and dolphins; manatees and dugongs; walruses; seals
a terrestrial or aquatic flesh-eating mammal
in some classifications considered a suborder of Carnivora
Orycteropus afer, aardvark, ant bear, anteater
nocturnal burrowing mammal of the grasslands of Africa that feeds on termites; sole extant representative of the order Tubulidentata
bat, chiropteran
nocturnal mouselike mammal with forelimbs modified to form membranous wings and anatomical adaptations for echolocation by which they navigate
gnawing mammal, lagomorph
relative large gnawing animals; distinguished from rodents by having two pairs of upper incisors specialized for gnawing
gnawer, rodent
relatively small placental mammals having a single pair of constantly growing incisor teeth specialized for gnawing
naked mole rat
fetal-looking colonial rodent of East Africa; neither mole nor rat; they feed on tubers and have a social structure similar to that of honeybees and termites
Damaraland mole rat
colonial mole rat of western Africa; similar to naked mole rat
in former classifications a major division of Mammalia comprising all hoofed mammals; now divided into the orders Perissodactyla (odd-toed ungulates) and Artiodactyla (even-toed ungulates)
hoofed mammal, ungulate
any of a number of mammals with hooves that are superficially similar but not necessarily closely related taxonomically
in former classifications a major division of Mammalia comprising mammals with nails or claws; distinguished from hoofed mammals and cetaceans
unguiculate, unguiculate mammal
a mammal having nails or claws
coney, cony, das, dassie, hyrax
any of several small ungulate mammals of Africa and Asia with rodent-like incisors and feet with hooflike toes
any of various nonruminant hoofed mammals having very thick skin: elephant; rhinoceros; hippopotamus
primitive terrestrial mammal with few if any teeth; of tropical Central America and South America
anteater, pangolin, scaly anteater
toothless mammal of southern Africa and Asia having a body covered with horny scales and a long snout for feeding on ants and termites
any placental mammal of the order Primates; has good eyesight and flexible hands and feet
tree shrew
insectivorous arboreal mammal of southeast Asia that resembles a squirrel with large eyes and long sharp snout
colugo, flying cat, flying lemur
arboreal nocturnal mammal of southeast Asia and the Philippines resembling a lemur and having a fold of skin on each side from neck to tail that is used for long gliding leaps
proboscidean, proboscidian
massive herbivorous mammals having tusks and a long trunk
plantigrade, plantigrade mammal
an animal that walks with the entire sole of the foot touching the ground as e.g. bears and human beings
digitigrade, digitigrade mammal
an animal that walks so that only the toes touch the ground as e.g. dogs and cats and horses
Type of:
craniate, vertebrate
animals having a bony or cartilaginous skeleton with a segmented spinal column and a large brain enclosed in a skull or cranium

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