- AURS (Automated Unit Reference Sheet)
- AUS (Australia (ISO 3166 trigram))
- AUSA (Association of the United States Army)
- AUSCANNZUKUS (Australia, Canada, New Zealand, United Kingdom, United States (security designation))
- Auslan (Australian Sign Language)
- AUSTACCS (Australian Tactical Automated Command and Control System)
- AUSTIN (Action, Understanding, Skills, Training, Integrity ,and Negotiation)
- AUT (Austria (ISO 3166 trigram))
- AUTEC (Atlantic Undersea Test and Evaluation Center)
- AUTH (Authority)
- Authen. (Authentica ("Authentic" e.g. letters))
- AUTL (Army Universal Task List)
- AUTO (Automatic)
- AUTOCOM (Automated Communicator)
- AUTODIN (Automatic Digital Network)
- AUTODN (Automatic Digital Network)
- AUTOROS (Automated Retail Outlet System)
- AUTOS (Annual Unit Training On-line System)
- AUTO-SEVOCOM (Automatic Secure Voice Communications (System))
- AUTOSTRAD (Automated System for Transportation Data)
- AUTOVON (Automatic Voice Network)
- AUU (Aurukun Airport)
- AUV (authonomus underwater vehicle)
- AUVA (Army Unmanned Aerial Vehicle)
- AUW (Wausau Downtown Airport)
- AUX (Araguaína Airport)
- Aux. (Auxilium, Auxilio ("Help", "With the help of"))
- AUXO (Auxiliaries Officer)