the GNU version of the Collaborative International Dictionary of English
noun-plural. 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.
The Century Dictionary and Cyclopedia
In zoology, the highest class of Vertebrata, containing all those animals which suckle their young, and no others; mammiferous animals; the mammals.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
n. warm-blooded vertebrates characterized by mammary glands in the female
Word Usage
"Grasps the nutrient organ whence the term mammalia,"