MAMMALIA

n. class of warm-blooded vertebrate animals which secrete milk to feed their young and have a covering of hair on their bodies

Mammals (class Mammalia) are warm-blooded, vertebrate animals characterized by the presence of sweat glands, including those that produce milk, and by the presence of: hair, three middle ear bones used in hearing, and a neocortex region in the brain. Most mammals also possess specialized teeth and utilize a placenta in the ontogeny. The mammalian brain regulates endothermic and circulatory systems, including a four-chambered heart. Mammals encompass approximately 5,400 species (including humans), distributed in about 1,200 genera, 153 families, and 29 orders, though this varies by classification scheme.
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Noun
1. warm-blooded vertebrates characterized by mammary glands in the female
(synonym) class Mammalia
(hypernym) class
(member-holonym) Vertebrata, subphylum Vertebrata, Craniata, subphylum Craniata
(member-meronym) young mammal

n. mammalia, class of animals that feeds its offspring from mother's milk

(n. pl.)
The highest class of Vertebrata. The young are nourished for a time by milk, or an analogous fluid, secreted by the mammary glands of the mother.