Di

Di or DI may refer to:

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

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