ND

ND may refer to:

Arts and media

• nD, a fictional alien species in Invasion: Earth (TV series)
• Nancy Drew, a fictional teenage sleuth in various media
• Naughty Dog, an American video game developer
• Notitia Dignitatum, a late Roman administrative codex
• Nuclear Dawn, a 2011 video game (once a Half-Life 2 mod)

Businesses

• Nextdoor, a hyperlocal social networking service for neighborhoods
• NetDocuments, a British document management company
• Norsk Data, a defunct Norwegian computer manufacturer

Language

• Nd (digraph), a digraph present in many African languages
• Northern Ndebele language, of Botswana and Zimbabwe (ISO 639-1:nd)

Places

• North Dakota, a state of the United States
• New Delhi, India's capital city
• Notre Dame (disambiguation), a number of churches and colleges
• Nguyen dynasty, unified Vietnamese empire (1802–1884)

Politics

• National Democracy (Poland), a political movement 1886–1947
• National Democrats (Sweden), a far-right party 2001–2014
• New Dawn (Algeria), a nationalist party formed in 2012
• New Democracy (Canada), an economic reform party 1939–1940
• New Democracy (Greece), a center-right party formed in 1974
• New Democracy (North Macedonia), a conservative ethnic Albanian party formed in 2008
• New Democrats (France), a left-wing party 2020–2022
• Nuclear disarmament, the dismantlement and proposed dismantling of nuclear weapons

Science and technology

Mathematics

• nd (elliptic function), one of Jacobi's elliptic functions

Medicine

• NADH dehydrogenase, an enzyme
• Non-distended, an abdominal distension clinical examination value
• Naturopathic Doctor, a degree in naturopathic medicine
• Notifiable disease, any disease that is required by law to be reported to government authorities

Physics

• ND Experiment, a particle physics experiment in Novosibirsk, Russia
• n_D, the refractive index of a medium at a wavelength of 589.8 nm

Other uses in science and technology

• Neighbor Discovery, an Internet protocol
• Neodymium, symbol Nd, a chemical element
• Neutral density filter, a type of filter used in photography
• Contax N Digital, a digital camera
• ND for nominal diameter in piping
• ND MX-5 Miata, the fourth generation of the Mazda MX-5

Weapons and military

• United States Navy Diver, an occupational rating
• Negligent discharge, a careless use of a firearm
• Norrland Dragoon Regiment, of the Swedish Army
• Nuclear disarmament, the proposed dismantling of nuclear weapons

Other uses

• National Diploma (Ireland), an academic qualification in the Republic of Ireland
• New Dawn (disambiguation), with various meanings
• Neurodiversity, variation in cognition and sociability (per the social model of disability)
• n.d. for "no date", an abbreviation used in APA-style and other styles of bibliographic citations
• in the International Code of Signals, denotes a tsunami warning