A

A stands for Absent
A stands for Absolute (degrees Kelvin)
A stands for Absorbance
A stands for Absorptance
A stands for Academy
A stands for Accelerating Contactor or Relay
A stands for Acceleration
A stands for Accept
A stands for Accommodation
A stands for Account
A stands for Accumulator
A stands for Accusative
A stands for Ace
A stands for Ace (used on playing cards)
A stands for Acre
A stands for Acronym
A stands for Action
A stands for Active
A stands for Activity
A stands for Add(ed) (action code)
A stands for Adenine (one of four DNA building blocks)
A stands for Adenosine
A stands for Adenylic Acid
A stands for Adjacent (to a carboxyl group; chemistry)
A stands for Adjective
A stands for Adjutant
A stands for Administration
A stands for Adultery (as in the Scarlet Letter)
A stands for Advanced
A stands for Advanced Digital Audio (filename extension)
A stands for Advanced Levels (highest level of academic boards, UK)
A stands for Aerial
A stands for Aft
A stands for Afternoon
A stands for Agency
A stands for Aggressive Personality Type
A stands for Agilent Technologies Incorporated (stock symbol)
A stands for Agouti
A stands for Agreed To (that an amendment or other matter was approved; US House)
A stands for Air Force training category (15 days active duty training per year)
A stands for Airbus
A stands for Aircraft
A stands for Airman
A stands for Airplane
A stands for Aktopia
A stands for Alanine
A stands for Algemeen
A stands for Aliphatic Chain (chemistry)
A stands for Allegro (game programming library)
A stands for Alpha
A stands for Alpha Particle
A stands for Alto
A stands for Alveolar Gas
A stands for Alwaya (dinnerware trademark)
A stands for Amateur
A stands for Amendment of Application (insurance)
A stands for American Bank Note Company (numismatic/philatelic)
A stands for Ampere
A stands for Amphibian (aircraft type)
A stands for Amplitude
A stands for Analog
A stands for Analog Signal

A stands for Analysis
A stands for Analysis and Assessment (LANL)
A stands for Anchor (HTML)
A stands for And
A stands for Angle of Asymmetry (NIOSH)
A stands for Angstrom (should be written with Å; unit of length)
A stands for Animaniacs
A stands for Anna
A stands for Anno
A stands for Annual
A stands for Annually
A stands for Anode
A stands for Anonymous
A stands for Answer
A stands for Ante (Latin: Before)
A stands for Anterior
A stands for Applanation Tension (pressure in the eye)
A stands for Apple
A stands for Applet
A stands for Approved
A stands for Aqua
A stands for Arc
A stands for Arctic
A stands for Are (unit of area)
A stands for Area
A stands for Argon
A stands for Army
A stands for Army (in combinations only)
A stands for Aromatic Substituent (chemistry)
A stands for Arse
A stands for Arterial blood
A stands for Arterial Road (used with road numbers)
A stands for Artery
A stands for Article
A stands for Artillery
A stands for Ask
A stands for Ass
A stands for Assay and Accountability (LANL)
A stands for Assembly Source Code (Macintosh filename extension)
A stands for Assist (Sports)
A stands for Assisted Citizen (Alabama Public Safety Radio Code)
A stands for Association
A stands for Asymmetric
A stands for At or Above (constrained altitude)
A stands for Atomic (as in A-bomb)
A stands for Atomic Mass
A stands for Attack (US military aircraft designation, as in A-10)
A stands for Atto-
A stands for Auditor
A stands for Auris (Latin: ear)
A stands for Australian
A stands for Austria (international car index mark)
A stands for Author
A stands for Automobile
A stands for Autostrada (Italian notation for highways)
A stands for Autotuned Navaid (aviation navigational aid)
A stands for Availability
A stands for Avance (French: fast)
A stands for Avianca Airlines (philatelic airmail overprint)
A stands for Away (Sports)