CI or Ci may refer to:
A city is a large and permanent human settlement. Although there is no agreement on how a city is distinguished from a town in general English language meanings, many cities have a particular administrative, legal, or historical status based on local law.
Cincinnati (/ˌsɪnsᵻˈnæti/ SIN-si-NAT-ee) is a city in the U.S. state of Ohio that serves as county seat of Hamilton County.
The circulatory system, also called the cardiovascular system or the vascular system, is an organ system that permits blood to circulate and transport nutrients (such as amino acids and electrolytes), oxygen, carbon dioxide, hormones, and blood cells to and from the cells in the body to provide nourishment and help in fighting diseases, stabilize temperature and pH, and maintain homeostasis.
Ciprofloxacin is an antibiotic used to treat a number of bacterial infections. This includes bone and joint infections, intra abdominal infections, certain type of infectious diarrhea, respiratory tract infections, skin infections, typhoid fever, and urinary tract infections, among others.
The cinema of India consists of films produced across India. Cinema as a medium has gained immense popularity in the country and as many as 1,600 films in various languages of India are produced annually.
A cigarette, or cigaret, is a small cylinder of finely cut tobacco leaves rolled in thin paper for smoking.
A circadian rhythm /sɜːrˈkeɪdiən/ is any biological process that displays an endogenous, entrainable oscillation of about 24 hours.