n. The fatty tissue that surrounds and protects the kidneys; that of sheep and cattle is used in cooking and in making tallow.
the GNU version of the Collaborative International Dictionary of English
n. The fat and fatty tissues of an animal, especially the harder fat about the kidneys and loins in beef and mutton, which, when melted and freed from the membranes, forms tallow.
The Century Dictionary and Cyclopedia
n. The fatty tissue about the loins and kidneys of certain animals, as the ox, the sheep, the goat, and the hart, harder and less fusible than that from other parts of the same animals.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
n. hard fat around the kidneys and loins in beef and sheep
Word Usage
"Many Christmas puddings contain suet, but my mother and her mother used butter, because they found suet unappetizing."