Di

Di or DI may refer to:

In arts and media

Di, a tone in the solfège ascending chromatic scale existing between Do and Re
Dizi (musical 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

Deseret Industries, an LDS thrift store
Destination ImagiNation, an international creative problem solving organization for children
Defensa Interior, an anti-Franco militant anarchist group in 1960s Spain
DynCorp International, a major United States defense contractor
Dimensional Insight, a business intelligence company
Discovery Institute, an intelligent design advocacy group
Dogwood Initiative, a Canadian non-profit public interest group based in Victoria, British Columbia

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

Di, a prefix used in organic chemistry nomenclature
Diameter, the distance across the middle of a circle
Didymium, a mixture of the elements praseodymium and neodymium once thought to be an element
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

Di (Wu Hu) (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

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, Princess of Wales (1961–1997), commonly known as Princess Di

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 impingement, a class of firearm gas operation mechanism
Direct Injection, a type of fuel injection
Diagnostic Imaging

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")

Direction Italy, a liberal-conservative political party in Italy
Di Department, one of the eight departments of the Sourou Province in Burkina Faso
501 (number) in Roman numerals
Democracy Index, compiled by the Economist Intelligence Unit
Detective Inspector, a police rank
Disability insurance, a form of insurance that insures the beneficiary's earned income against the risk that a disability will make working uncomfortable
Disposable Income, total personal income minus personal current taxes
Document of Identity, issued by the Hong Kong Immigration Department
Drill instructor, a non-commissioned officer in many military or police forces