| A&C | Admin & Clerical 
| Others |
| A&C | Administrative & Clerical
| Others |
| A&C | Alesaggio e Corsa
| Others |
| A&C | Antique and Classic
| Others |
| A&CO | Assembly and Checkout Operation
| Others |
| A&D | Admission and Disposition (report)
| Others |
| A&D | Aerospace and Defence
| Others |
| A&D | Aerospace and Defense
| Others |
| A&D | Alcohol and Drugs
| Others |
| A&D | Auto and Design
| Others |
| A&DSL | Administrative and Direct Support Logistics
| Others |
| A&E | Accident & Emergency
| Others |
| A&E | Accident & Emergency (UK)
| Others |
| A&E | Accident and Emergency
| Others |
| A&E | Aircraft and Engine
| Others |
| A&E | Architects and Engineering
| Others |
| A&E | Architectural and Engineering
| Others |
| A&E | Architecture and Engineering
| Others |
| A&E | Arts & Entertainment
| Others |
| A&E | Arts and Entertainment
| Others |
| A&E | Automotive and Engineering
| Others |
| A&F | Abercrombie & Fitch
| Others |
| A&F | Air and Fuel
| Others |
| A&H | Acura and Honda
| Others |
| A&HCI | Arts and Humanities Citation Index
| Others |
| A&I | Allergy and Immunology
| Others |
| A&I | Assembly & Installation
| Others |
| A&I | Assembly and Installation
| Others |
| A&J | Acceleration and Jerk
| Others |
| A&L | Approach and Landing
| Others |
| A&L | Assets and Liabilities
| Others |
| A&M | Agricultural & Mechanical
| Others |
| A&M | Agricultural & Mining
| Others |
| A&M | Approach and Methodology
| Others |
| A&M | Audio and Music Data
| Others |
| A&M | Automatic and Manual
| Others |
| A&O | Alert and Orientated
| Others |
| A&O | Alert and Oriented
| Others |
| A&O | Aware and Oriented
| Others |
| A&O or A/O | aware and oriented or alert and oriented
| Others |
| A&O x4 | Alert & Oriented, Times 4 (to person, place, time, and circumstances)
| Others |
| A&Ox3 | alert and oriented, times 3 (to person, place, and time)
| Others |
| A&P | Administrative and Personal
| Others |
| A&P | Administrative and Personnel
| Others |
| A&P | Advertising & Promotion
| Others |
| A&P | Air frame and Power plant
| Others |
| A&P | Analysis and Prediction
| Others |
| A&P | Anterior and Posterior
| Others |
| A&P | Atlantic and Pacific
| Others |
| A&P | Attitude and Pointing
| Others |