# Di

Di or DI may refer to:

## Arts and media
### Music

* Di, a tone in the solfège ascending chromatic scale existing between Do and Re
* dizi (instrument) or di, a Chinese transverse flute
* D.I. (band), a punk band from Southern California
** D.I. (EP), a 1983 EP by the same band above

### Other media

* The D.I., 1957 military film by Jack Webb
* Dagens Industri, a Swedish financial newspaper
* DI.FM, an internet radio service

## Businesses and organisations

* Defence Intelligence, a UK military intelligence agency
* Defensa Interior, an anti-Franco militant anarchist group in 1960s Spain
* Deseret Industries, an LDS thrift store
* Desert Inn, a former casino in Las Vegas
* Direction Italy, a liberal-conservative political party in Italy
* Dirgantara Indonesia, an Indonesian aircraft company
* Discovery Institute, an intelligent design advocacy group
* Marabu (airline) (IATA code: DI), an Estonian leisure airline
* Norwegian Air UK (former IATA code: DI), a former UK airline
* DBA (airline) (former IATA code: DI), a former German low-cost airline
* DynCorp International, a major United States defense contractor
* Myanmar Directorate of Defence Industries

## Education

* Diplomi-insinööri, a Finnish 6-year engineering degree
* Direct instruction, an instructional method focused on a systematic curriculum design

## Natural sciences

* Di, a prefix used in organic chemistry nomenclature
* Didymium, a mixture of the elements praseodymium and neodymium once thought to be an element
* Diopside, a clinopyroxene mineral
* Band 3, a protein
* Deionized water, a type of water deprived of the dissolved impurities of ionic nature
* Diabetes insipidus, a disease
* Iodothyronine deiodinase type I, one of a subfamily of enzymes important in the activation and deactivation of thyroid hormones
* Dentinogenesis imperfecta a genetic disorder of tooth development

## People
### Ethnic groups

* Di (Five Barbarians) (氐), an ethnic group that overran northern China during the Sixteen Kingdoms period
* Beidi or Northern Di (狄), ethnic groups living in northern China during the Zhou Dynasty

### Individuals

* Di (surname) (狄), a Chinese surname sometimes also romanized Dee, particularly:
** Di Renjie a Tang-dynasty official later fictionalized in a series of Chinese detective stories
* A diminutive form of the names:
** Diana (given name)
** Diane (disambiguation)
** Dianne (disambiguation)
* Diana, Princess of Wales (1961–1997), commonly known as Princess Di or Lady Di

## Technology

* Digital intermediate, a filmmaking post-production process
* Dependency injection, a method of decoupling components in software
* DI unit or Direct Input box, an audio device used with PA systems and in sound recording studios
* DI register, or destination index, in x86 computer architecture
* Direction indicator, an instrument in aviation also known as a heading indicator
* Direct ignition, see Distributor § Direct ignition
* Direct injection, a type of fuel injection

## Religion

* di (帝), a Chinese word employed in
** the temple names of deified Chinese emperors
** Shangdi (Chinese: 上帝, lit. "Lord on High"), the Chinese name for the supreme sky god either in native Chinese beliefs or in translation of monotheistic faiths like Christianity and Islam
* di (Chinese concept) (地), the concept of "earth" in traditional Chinese cosmologies
* di, an irregular Latin masculine plural of deus ("god", "deity")

## Other uses

* Detective Inspector, a rank in certain police forces
* Di (cuneiform), an ancient written sign
* Diameter, the distance across the middle of a circle
* Di Department, one of the eight departments of the Sourou Province in Burkina Faso
* 501 (number) in Roman numerals
* Disability insurance, a form of insurance that insures the beneficiary's earned income against the risk that a disability will make working uncomfortable
* Hong Kong Document of Identity, issued by the Hong Kong Immigration Department
* Drill instructor, a non-commissioned officer in many military or police forces
* Differentiated integration, a mechanism for the European Union's countries to opt out of EU policies