A3

For the Wikipedia A3 criteria for speedy deletion, see Wikipedia:Criteria for speedy deletion#A3.

A3, A03, A-3, A.3, A.III or A 3 may refer to:

In business

• A3 paper, a paper size defined by ISO 216 (297 × 420 mm)
• A structured problem solving and continuous improvement approach, first employed at Toyota, and typically used by Lean practitioners.

In biology

• A3 regulatory sequence, a sequence for the insulin gene
• Adenosine A₃ receptor, a human gene
• Annexin A3, a human gene
• ATC code A03 Drugs for functional gastrointestinal disorders, a subgroup of the Anatomical Therapeutic Chemical Classification System
• Brachydactyly type A3, a disease
• British NVC community A3 (Spirodela polyrhiza - Hydrocharis morsus-ranae community), a British Isles plants community
• Gibberellin A3, a plant hormone
• HLA-A3, a Human MHC Serotype HLA-A
• Subfamily A3, a rhodopsin-like receptors subfamily
• Urea transporter A3, a trans-membrane protein

In games

• A3 - Assault on the Aerie of the Slave Lords, a 1981 module for the Dungeons & Dragons fantasy role-playing game
• A.III, A-Train III, a 1992 computer game
• Alpha Trion, as the former name of this character from the Transformers Series
• A03, Encyclopaedia of Chess Openings code for Bird's Opening

In mathematics

• A₃ is an example of a root system with numerous physical and geometrical applications

In roads

• A3 roads, in several countries

In sports

• A3 Champions Cup, a club football tournament also known as the East Asian Champions Cup
• Arrows A3, a 1980 racing car
• a Grade (climbing), to a route that concisely describes the difficulty and danger of climbing the route. Different aspects of climbing each have their own grading system, and many different nationalities developed their own, distinctive grading systems

In vehicles

• A-3 lifeboat, a 1947 lifeboat for carrying by the SB-29 Superfortress
• Abrial A-3 Oricou, a French touring aircraft designed in 1927
• Audi A3, a model of automobile
• Aussat (Optus) A3, a 1987 Australian telecommunication satellite
• Bavarian A III, a 1851 German steam locomotive model
• LNER Gresley Classes A1 and A3, a Pacific Locomotive Designed by Sir Nigel Gresley
• PRR A3, an American PRR 0-4-0 steam locomotive
• Prussian A 3, a 1910 German railbus
• SP&S Class A3, a 1914 steam locomotives class

In weapons or military

• A-3 Falcon, a variant of the Curtiss Falcon, an attack aircraft manufactured by the Curtiss Aircraft Company
• A-3 Skywarrior, a strategic bomber manufactured by Douglas Aircraft Company
• AUG A3, a variant of the Austrian Steyr AUG rifle
• Focke-Wulf A 3, a WWI German Focke-Wulf aircraft
• Fokker A.III, a 1915 armed version of the Fokker M.5 aircraft
• HMS A3, a British A class submarine of the Royal Navy
• Kampfgeschwader 200, from its historic Geschwaderkennung code with the Luftwaffe in World War II
• M16A3, a variant of the American M16 rifle
• M60A3, a variant of the American M60 Patton tank
• Polaris A-3 missile, an American submarine-launched missile
• Wendes artilleriregemente designation, a former Swedish Army artillery regiment
• A3, the staff designation for air force headquarters staff concerned with operations
  • In the United Kingdom, the A3 Air Operations Branch of the Joint Force Air Component Headquarters
• USS Grampus (SS-4), a Plunger class submarine of the United States Navy
• A3J, the original designation of the US Navy's A-5 Vigilante bomber
• Aggregate 3, the 3rd design in the Aggregate family of rockets, precursor to the V-2 rocket, developed by the Germans during World War II

In music

• a musical note, the A below Middle C
• Alabama 3, a band known as A3 in the U.S. to avoid confusion with the country group Alabama
• A-3, a Yamaha combo organ
• Alkaline Trio, a rock band

In government

• A-3 visa, a document given to employees of A-1 and A-2 Visa Holders who are representing a foreign government inside the United States of America
• In town and country planning in the United Kingdom, A3 is the code for permission to use specific land or premises for restaurants and cafés

other

• A-003, the fourth abort test of the Apollo spacecraft
• Biu-Mandara A.3 languages, an Afro-Asiatic family of languages mainly spoken in Far North Province, Cameroon as well as in Adamawa State, Nigeria
• Cowon A3, an audio media player
• The IATA code for Aegean Airlines
• Tonga aircraft registration code
• ARITH-MATIC, as the former name for this programming language
• A3 (disambiguation), research chemical
• A3, an abbreviation of "Agora! Anarchy! Action!", a popular slogan for Agorism taken from the New Libertarian Manifesto by Samuel Edward Konkin III