CI or Ci may refer to:

Business terminology

  • Commercial invoice
  • Competitive intelligence
  • Confidential information
  • Continual improvement
  • Corporate identity
  • Customer intelligence, a discipline in marketing

Businesses and organisations

Academia and education

  • California State University, Channel Islands
  • Channel Islands High School
  • Collegium Invisibile
  • Confucius Institute

Religion

  • Josephites of Belgium, a Catholic congregation
  • Christian Identity
  • Christian Institute, a British charity which promotes Christian values

Other businesses and organizations

  • CI Financial, Canadian investment management company
  • Charity Intelligence Canada
  • China Airlines (IATA code)
  • Cigna health services (NYSE symbol)
  • Consumers International
  • Cycling Ireland
  • CI Records, a music record label
  • Cambria and Indiana Railroad
  • CANZUK International, organisation which promotes cooperation between Canada, Australia, New Zealand and the United Kingdom
  • Conservation International, an international environmental non-governmental organization
  • Communications International, a former global union federation
  • Communist International
  • Children International, a non-profit child sponsorship organization
  • Cryonics Institute, American nonprofit foundation

Law and military

  • Counterintelligence
  • Confidential informant
  • Compliance Inspection, a United States Air Force inspection
  • Chief inspector, a police rank
  • Circle inspector, a junior police rank
  • Certificate of identity
  • Civilian Internee, a special status of a prisoner during wartime
  • Civilian Instructor, an adult volunteer in the British Air Training Corps and Canada Air Cadets

Places

  • Ci County, in Hebei, China
  • Cayman Islands
  • Chile (FIPS country code, obsolete NATO country code)
  • Coney Island
  • Cocos (Keeling) Islands, an external territory of Australia
  • Cook Islands, an island-country in the South Pacific Ocean
  • Côte d'Ivoire (ISO country code)
  • Channel Islands
  • Channel Islands of California
  • Carbonia-Iglesias, a province in southern Italy
  • Central India, region of India, abbreviated CI
  • Central India Circuit or C. I. Circuit, a Hindi film distribution circuit comprising parts of Madhya Pradesh (Indian state within central India)
  • Central Islip, New York, a hamlet on Long Island, New York in the United States

Science, technology and mathematics

Biology and medicine

  • cI protein, a repressor protein of Enterobacteria phage λ
  • Cytoplasmic incompatibility, a reproductive system
  • Cardiac index
  • Ci protein, Cubitus interruptus -protein
  • Coital incontinence
  • Convergence insufficiency
  • Corpulence index
  • Cumulative incidence, used as a measure of disease frequency in epidemiology
  • Cochlear implant
  • Chemical injury syndrome, an increased sensitivity to common chemicals also called multiple chemical sensitivity.
  • Chronic illness, a condition that is long-lasting or recurrent
  • Contraindication

Computing

  • .ci, the Internet country code top-level domain (ccTLD) for Côte d'Ivoire
  • Common Interface, for a Conditional Access Module
  • CI+, Common Interface Plus
  • Computational intelligence
  • Configuration item, the fundamental structural unit of a configuration management system
  • Core Image, non-destructive image processing technology
  • Continuous integration, a software-engineering practice of merging developer code into a main code base frequently
  • CodeIgniter, a PHP framework

Earth science

  • Cirrus cloud
  • Convective instability

Mathematics

  • Conditional independence, a type of relation of random variables in probability theory
  • Confidence interval, an interval estimate of a population parameter used in statistics
  • 101 (number) (in Roman numerals)
  • Compound interest
  • Cosine integral (standard mathematical symbols "Ci" and "ci")

Physics

  • Conical intersection, the location of a discrete degeneracy between two electronic states
  • Curie (unit) (Symbol: Ci), a measurement of radioactivity named after Marie Curie
  • Copenhagen interpretation, an interpretation of quantum mechanics
  • Cubic inch, a unit of volume

Other uses in science and technology

  • CI group, a type of carbonaceous chondrite meteorite
  • Carrier interferometry, a radio and optical communication coding technology
  • Chemical ionization, a technique used in mass spectrometry
  • Configuration interaction, a post-Hartree–Fock method used in computational chemistry
  • Contextual inquiry, a user-centered design research method
  • Collective intelligence, a subfield of sociology
  • Colour Index International, a reference database of CI numbers for dyes and pigments
  • Bavarian C I, a steam locomotive with the Royal Bavarian State Railways
  • Compression ignition engine, another name for a diesel engine
  • Cost Index (CI), the ratio of time cost to fuel cost, used to calculate the cruising speed of an airliner

Television

  • Canadian Idol, a Canadian television series
  • Law & Order: Criminal Intent, an American television series
  • Crime & Investigation Network
  • Crime & Investigation Network (Australia), Australian cable and satellite network focusing on Crime
  • Crime & Investigation Network (Europe), a pan-European television channel
  • Crime & Investigation Network (South East Asia)

Other uses

  • Ci (poetry), a form of Chinese lyric poetry
  • Qi, a central concept in several eastern philosophies
  • Categorical imperative, in philosophy
  • Colour Index International, a reference database
  • Comprehensible input
  • Contact improvisation, a dance technique
  • CI, postnominal for Companion of the Order of the Crown of India
  • Ci, a form of the surname Qi, of the Tungusic peoples

See also

  • C1 (disambiguation)
  • Cl (disambiguation)