# CA

CA most often refers to:
* Canada, a country by ISO 3166-1 alpha-2 code
* California, U.S. state by postal abbreviation
CA or ca may also refer to:

## Businesses and organizations
### Companies

* Air China (IATA airline code CA)
* CA Technologies, a U.S. software company
* Cayman Airways, a Cayman Islands airline
* Channel America, a defunct U.S. television network
* Coal & Allied, Australian mining company
* Continental Airlines, a U.S. airline
* Creative Assembly, a PC game developer
* Crédit Agricole, a major French bank

### Government and political

* Bureau of Consular Affairs, a division of the U.S. Department of State
* Canadian Alliance, a former Canadian political party
* Centre Alliance, Australian political party formerly known as Nick Xenophon Team
* Citizens' Alliance, a political party in Trinidad and Tobago
* Combined authority, a local government entity in the United Kingdom
* Commission on Appointments, a body of the Congress of the Philippines
* Conservatives Abroad, overseas wing of the British Conservative Party
* Countryside Alliance, a British political organization
* Court of Appeals
* Customs Administration, an agency of Taiwan

### Schools

* Canadian Academy, an international school in Kobe, Japan
* Cary Academy, a private college-preparatory school in Cary, North Carolina, United States
* Claiborne Academy, a private school in Claiborne Parish, Louisiana, United States
* Clarksville Academy, a private college-preparatory school in Clarksville, Tennessee, United States
* Colorado Academy, a private college-preparatory school in Lakewood, Colorado, United States
* Concord Academy, a private college-preparatory school in Concord, Massachusetts, United States
* Connections Academy, an online school based in Baltimore, Maryland, United States
* Culver Academies, a boarding school and summer camp program in Culver, Indiana, United States

### In sport

* California Angels, former name of a professional baseball team currently known as Los Angeles Angels
* Club Africain, a multi-sport club from Tunis, Tunisia
* Cricket Australia, the governing body for professional and amateur cricket in Australia
* Cruising Association, a UK membership organization for sailors
* Cycling Australia, the national governing body for bicycle racing in Australia

### Other organizations

* Caterers' Association, former UK trade association
* Cocaine Anonymous, a twelve-step program
* Creativity Alliance, an arm of Creativity (religion), a white supremacist organization

## In linguistics

* Ca., an abbreviation for circa, meaning "approximately" in Latin
* Ça, French demonstrative pronoun
* Ca (Indic), a glyph in the Brahmic family of scripts
* Ca (Javanese), a letter in the Javanese script
* Catalan language (ISO 639 alpha-2 language code)
* ca, the subdomain for Catalan Wikipedia
* Contrastive analysis, the systematic study of a pair of languages

## Mathematics, science, and technology
### Biology and medicine

* CA (journal), a medical journal
* Ca (moth), a moth genus
* Ca., abbreviation for Candidatus, for taxonomical names that have not been completely described
* Cancer
* Carbonic anhydrase, a family of enzymes
* Carcinoma, a type of cancer
* Cardiac arrest

### Chemistry

* Calcium, symbol Ca, a chemical element
* Catecholamine, an organic compound
* Cellulose acetate, a type of plastic
* Chemical Abstracts, a publication of Chemical Abstracts Service
* Cyanoacrylate, a chemical compound

### Mathematics and computing

* Cellular automaton, a discrete mathematical model
* Certificate authority, an entity issuing digital certificates for secure communications
* Correspondence analysis, a multivariate statistical technique
* Cultural algorithm, a type of evolutionary computation in computer science

### Other uses in science and technology

* Centiampere (cA), an SI unit of electric current
* Certificate Authority (CA), an entity that issues digital certificates
* CA-class submarine, a World War II Italian midget submarine
* Nissan CA engine, used in smaller Nissan vehicles
* Chromatic aberration, a distortion in optical lenses
* Conditional access, in broadcast engineering
* Conservation agriculture, a food system
* Conversation Analysis, the study of talk in interaction

## Places

* Cả River, in Laos and Vietnam
* Province of Cádiz, Spain
* City of Carlisle, United Kingdom, by postcode
* Catamarca Province, Argentina
* Central America
* Tokyo Bay Aqua-Line, a bridge-tunnel across Tokyo Bay area in Japan, numbered as CA

## Other uses

* .ca, Internet country code for Canada
* CA-, a road designation for highways part of the Central American highway network
* CA, the official designation for heavy cruiser in the U.S. Navy from 1920–1945
* 'CA': Tactical Naval Warfare in the Pacific 1941-43, a 1973 board wargame that simulates World War II naval combat
* Ca Mè Mallorquí, a dog breed native to Spain
* centiare = 1 square metre
* Character assassination, a deliberate and sustained effort to damage the reputation or credibility of an individual
* Chartered Accountant
* Civil affairs, a term used by both the United Nations and by military institutions
* Communication arts (disambiguation)
* Confidentiality agreement
* Compañía Anónima, a type of corporate organization in Venezuela
* Current account (disambiguation), in economics
* A US Navy hull classification symbol: Heavy cruiser (CA)