# CD (disambiguation)

A CD or compact disc is a thin plastic silvery disc for audio recordings.
CD or cd may also refer to:

## Science and technology
### Astronomy and cosmology

* Cordoba Durchmusterung, a star catalog of the southern sky
* Cosmological decade or CÐ, a unit of time
* Type-cD galaxy, a galaxy morphology classification

### Biology, ecology, and medicine

* Coeliac disease, long term autoimmune disorder causing intolerance to gluten
* Conduct disorder, a psychological disorder
* Conservation Dependent or LR/cd, an IUCN category
* Cluster of differentiation, a protocol used for the identification of cell surface molecules on white blood cells
* Crohn's disease
* Chlordane
* Communicable disease

### Computing

* CD-ROM, compact disc technology applied for use in computer data
* cd (command), a command line command to change the current working directory in operating systems
* continuous delivery, a software development design practice
* continuous deployment, a software development design practice
* collision detection, CSMA/CD

### Mathematics

* cd (elliptic function), one of Jacobi's elliptic functions

### Other uses in science and technology

* Cadmium, symbol Cd, a chemical element
* Candela or cd, a unit of light intensity
* -CD, the North American call sign suffix for Class A low-power television stations operating with digital signals
* Circular dichroism, a form of spectroscopy
* Critical Dimension, the minimum feature size that a projection system can print in photolithography
* Drag coefficient or c$_d$, a dimensionless quantity used to quantify the drag of an object in a fluid
* Cluster decay, a rare mode of nuclear decay

## Businesses and organizations
### Government, military, and political

* Canadian Forces' Decoration, by post-nominal letters
* Centre Democrats (Denmark), a Danish former political party
* Centre Democrats (Netherlands), a former political party of the Netherlands
* Centro Democratico, a political party in Italy
* Christian democracy, a political ideology
* Civil defense, an effort to protect the citizens of a state from military attack and natural disasters
* Community of Democracies, an intergovernmental organization of democracies and democratizing countries
* Conference on Disarmament, an international forum that negotiates multilateral arms control and disarmament agreements
* Corps Diplomatique, the collective body of foreign diplomats accredited to a particular country or body
* FBI Counterintelligence Division, the United States Federal Bureau of Investigation's division responsible for investigating espionage

### Other business and organizations

* Certificate of deposit, a bank account in the United States with a fixed maturity date
* České dráhy or ČD, a railway operator of the Czech Republic
* Commander of the Order of Distinction, a rank in the Jamaican Orders of Societies of Honour

## Places

* Central District, Seattle, a district in Seattle
* Democratic Republic of the Congo, by ISO 3166-1 alpha-2 country code
** .cd, the Internet domain of the Democratic Republic of the Congo
* cd., abbreviation for caddesi, street, in Turkish

## Other uses

* 400 (number), written CD in Roman numerals
* 205 (number), written CD in hexadecimal
* AD 400 (CD), a year of the Common Era
* C.D (Criminal or Devil), a psychological thriller movie
* "CD", a song by T2 (band)
* cd, for cord (unit) of volume of wood
* Geely CD, a coupe automobile made by Geely Automobile
* Cairo Damascus or Damascus Document, a text found among the Dead Sea Scrolls
* Committee Draft, a status in the International Organization for Standardization
* Companion dog (title), a title offered to dogs by the American Kennel Club for dog obedience
* Cross-dressing, the act of wearing clothing associated with the opposite sex
* Corendon Dutch Airlines (IATA code)
* Sega CD, also known as the Sega Mega-CD, a CD-ROM accessory and format for the Sega Genesis produced by Sega as part of the fourth generation of video game consoles
** Sonic CD, a 1993 platform game developed and published by Sega for the Sega CD
* Bitter CD, a luxury hatchback coupé
* Cúcuta Deportivo, a Colombian football club