mammal

n. member of the class Mammalia (class of warm-blooded vertebrate animals the female of which secrete milk to feed their young and characterized by 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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(n.)
One of the Mammalia.
  

Noun
1. 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
(hypernym) vertebrate, craniate
(hyponym) female mammal
(member-holonym) Mammalia, class Mammalia
(part-meronym) coat, pelage
(class) digitigrade