# AD (disambiguation)

AD (Anno Domini) is a designation used to label years following 1 BC in the Julian and Gregorian calendars.
Ad (advertisement) is a form of marketing communication.
AD, A.D. or Ad may also refer to:

## Art, entertainment, and media
### Film and television

* A.D. (film), a 2010 animated zombie horror film
* A.D. (miniseries), a 1985 television miniseries set in ancient Rome
* A.D. The Bible Continues, a 2015 biblical drama television miniseries
* Arrested Development, an American television sitcom
* Attarintiki Daredi, 2013 Indian film by Trivikram Srinivas
* Audio description, a service for visually impaired audience on some TV programs

### Music

* AD (band), a Christian rock band
* A.D. (album), by Solace

### Publications

* AD (poem), by Kenneth Fearing
* A.D.: New Orleans After the Deluge, a nonfiction graphic novel about Hurricane Katrina
* Algemeen Dagblad, a Dutch newspaper
* Architectural Digest, an interior design and landscaping magazine

### Other art, entertainment, and media

* Audio description track, a narration track for visually impaired consumers of visual media

## Brands and enterprises

* Alexander Dennis, a British bus manufacturer
* Akcionersko društvo (aкционерско друштво), a Macedonian name for a type of company
* Aktsionerno drujestvo (акционерно дружество), a Bulgarian name for a type of company
* akcionarsko društvo (aкционарско друштво), a Serbian name for a type of company
* Analog Devices, a semiconductor company

## Educational qualifications

* Artist diploma, a music performance certificate conferred by higher education institutions.

## Military

* Accidental discharge, a mechanical failure of a firearm causing it to fire
* Active duty, a status of full duty or service, usually in the armed forces
* Air defense, an anti-aircraft weaponry and systems
* Air Department, part of the British Admiralty
* A US Navy hull classification symbol: Destroyer tender (AD)
* AD Skyraider, former name of the Douglas A-1 Skyraider, a Navy attack aircraft

## Organizations

* Action Directe, a French far-left militant group
* Democratic Action (Venezuela) (Spanish: Acción Democrática), a social democratic and center-left political party
* Democratic Alliance (Portugal, 1979) (Portuguese: Aliança Democrática), a former centre-right political alliance
* Democratic Alternative (Malta) (Maltese: Alternattiva Demokratika), a green political party

## People

* Ad (name), a given name, and a list of people with the name
* ‘Ad, great-grandson of Shem, son of Noah
* Anthony Davis (born 1993), American basketball player
* A. D. Loganathan (1888–1949), officer of the Indian National Army
* A. D. Whitfield (born 1943), American football player
* A. D. Winans (born 1936), American poet, essayist, short story writer and publisher
* A.D., nickname of Adrian Peterson (born 1985), American football player

## Places

* AD, ISO 3166-1 country for Andorra
* Abu Dhabi, capital of the United Arab Emirates
* AD, herbarium code for the State Herbarium of South Australia
* Andhra Pradesh, a state in southern India (HASC code)

## Professions

* Art director, for a magazine or newspaper
* Assistant director, a film or television crew member
* Athletic director, the administrator of an athletics program

## Science and technology
### Biology and medicine

* Addison's disease, an endocrine disorder
* Adenovirus, viruses of the family Adenoviridae
* Alzheimer's disease, a neurodegenerative disease
* Anaerobic digestion, processes by which microorganisms break down biodegradable material
* Anti-diarrheal, medication which provides symptomatic relief for diarrhea
* Aortic dissection, which occurs when an injury to the innermost layer of the aorta allows blood to flow between the layers of the aortic wall, forcing the layers apart
* Approximate digestibility, an index measure of the digestibility of animal feed
* Atopic dermatitis, form of skin inflammation
* Atypical depression, a type of depression
* Autosomal dominant, a classification of genetic traits
* Autonomic dysreflexia, a potential medical emergency

### Chemistry

* Adamantyl, abbreviated "Ad" in organic chemistry
* Sharpless asymmetric dihydroxylation, a type of organic chemical reaction

### Computing

* .ad, the top level domain for Andorra
* Administrative distance, a metric in routing
* Active Directory, software for the management of Microsoft Windows domains
* Administrative domain, a computer networking facility
* Analog-to-digital converter, a type of electronic circuit
* Automatic differentiation, a set of computer programming techniques to speedily compute derivatives
* AD$_{16}$, the hexadecimal number equal to decimal number 173

### Mathematics

* Adjoint representation of a Lie group, abbreviated "Ad" in mathematics
* Axiom of determinacy, a set theory axiom

### Physics

* Antiproton Decelerator, a device at the CERN physics laboratory
* Autodynamics, a physics theory

### Other uses in science and technology

* Active disassembly, a technology supporting the cost-effective deconstruction of complex materials

## Transportation

* AD, IATA code for:
** Air Paradise, a defunct Indonesian airline
** Azul Brazilian Airlines
* Airworthiness Directive, an aircraft maintenance requirement notice

## Other uses

* ʿĀd, an ancient Arab tribe, mentioned in the Quran
* Aggregate demand, in macroeconomics
* Anno Diocletiani, an alternative year numbering system
* United States Academic Decathlon, a high school academic competition