dozen

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

• noun A set of 12.
• noun An indefinite, large number.
• adjective Twelve.

from The Century Dictionary.

• noun A collection of twelve things; twelve units: used with or without of: as, a dozen eggs, or a dozen of eggs; twelve dozen pairs of gloves.
• noun In old English law, a municipal district consisting originally of twelve families or householders. Compare tithing, riding, hundred.
• To make up into bundles of twelve, as certain kinds of dressed hides.

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

• noun A collection of twelve objects; a tale or set of twelve; with or without of before the substantive which follows.
• noun An indefinite small number.
• noun thirteen; -- called also a long dozen.

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

• noun countable A set of twelve.
• noun A large, unspecified number of, comfortably estimated in small multiples of twelve, thus generally implied to be significantly more than ten or twelve, but less than perhaps one or two hundred; many.
• noun metallurgy An old English measure of ore containing 12 hundredweight.

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

• noun the cardinal number that is the sum of eleven and one
• adjective denoting a quantity consisting of 12 items or units