chestnut

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun Any of several deciduous trees of the genus Castanea native to northern temperate regions, having alternate simple toothed leaves, and nuts that are enclosed in a prickly husk.
• noun The often edible nut of any of these trees.
• noun The wood of any of these trees.
• noun Any of several other plants, such as the horse chestnut.
• noun A moderate to deep reddish brown.
• noun A reddish-brown horse.
• noun A small hard callus on the inner surface of a horse's foreleg.
• noun An old, frequently repeated joke, story, or song.
• adjective Of a moderate to deep reddish brown.

from The Century Dictionary.

• noun The fruit of trees of the genus Castanea. See 2.
• noun The tree Castanea vesca, natural order Cupuliferœ, a native of western Asia, southern Europe, and the United States east of the Mississippi.
• noun A name given to certain trees or plants of other genera, and to their fruit. See below.
• noun The color of a chestnut; a reddish-brown color.
• noun In farriery, the bur or horny wart-like excrescence on the inner side of a horse's leg.
• noun [In allusion to a stale or worm-eaten chestnut.] An old joke; a trite jest; a stale pun or anecdote; a “Joe Miller.”
• noun A worn-out phrase or catchword; a phrase or expression serious in form and intent, but which has ceased, through futile repetition, to command interest or respect.
• Of the color of a chestnut; of a reddish-brown color; castaneous.
• Also spelled chesnut.

from the GNU version of the Collaborative International Dictionary of English.

• adjective Of or pertaining of a chestnut; of a reddish brown color.
• noun (Bot.) The edible nut of a forest tree (Castanea vesce) of Europe and America. Commonly two or more of the nuts grow in a prickly bur.
• noun The tree itself, or its light, coarse-grained timber, used for ornamental work, furniture, etc.
• noun A bright brown color, like that of the nut.
• noun The horse chestnut (often so used in England).
• noun One of the round, or oval, horny plates on the inner sides of the legs of the horse, and allied animals.
• noun Slang An old joke or story.
• noun a tree that bears chestnuts.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A tree or shrub of the genus Castanea.
• noun The nut of this tree or shrub.
• noun uncountable A dark, reddish-brown colour/color.
• noun A reddish-brown horse.
• noun uncountable The wood of a chestnut tree.
• noun idiomatic (Often "old chestnut") A worn-out meme; a work so often repeated as to have grown tiresome.
• noun A part of a horse found on the inner leg, similar to a birthmark on a human.
• adjective Of a deep reddish-brown colour, like that of a chestnut.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun edible nut of any of various chestnut trees of the genus Castanea
• noun any of several attractive deciduous trees yellow-brown in autumn; yield a hard wood and edible nuts in a prickly bur
• adjective (of hair or feathers) of a golden brown to reddish brown color
• noun a small horny callus on the inner surface of a horse's leg
• noun wood of any of various chestnut trees of the genus Castanea
• noun a dark golden-brown or reddish-brown horse
• noun the brown color of chestnuts