cd

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

• abbreviation candela
• abbreviation cord

from The Century Dictionary.

• noun The chemical symbol for cadmium.
• noun In anatomy, an abbreviation used in vertebral formulas for caudal, or coccygeal: as, cd. 12 (that is, 12 caudal vertebræ).
• An abbreviation of the French carte de visite (visiting-card).

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

• noun the chemical suymbol for cadmium, a metallic element of atomic number 48.
• noun abbr. the abbreviation for the candela, the basic unit of luminous intensity adopted under the System International d'Unites.
• noun an acronym for compact disk, a disk-shaped recording of binary data that is smaller than a phonograph record, and is recorded and played back by a compact disk player, an electronic device containing a laser. The term is also used generically to refer to the medium as a data storage medium.
• noun informal a compact disk player.
• noun an acronym for certificate of deposit, a debt instrument issued by a bank for a fixed time period, usually paying interest.

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

• noun metrology Symbol for the candela, an SI unit of luminous intensity.
• noun A Roman numeral representing four hundred (400).

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

• adjective being one hundred more than three hundred
• noun a debt instrument issued by a bank; usually pays interest
• noun a soft bluish-white ductile malleable toxic bivalent metallic element; occurs in association with zinc ores
• noun the basic unit of luminous intensity adopted under the Systeme International d'Unites; equal to 1/60 of the luminous intensity per square centimeter of a black body radiating at the temperature of 2,046 degrees Kelvin
• noun a digitally encoded recording on an optical disk that is smaller than a phonograph record; played back by a laser