| Abbreviation | Definition |
|---|---|
| AC | Alternating Current |
| AC | Analog Computer |
| ac | analogue computer |
| AC | Audio Computer |
| ACAP | Advanced Common Application Platform |
| ACCIS | Army Command and Control Information System |
| ACCS | Advanced Computerized Color Scanner |
| ACD | Apple Cinema Display |
| ACD | Automatic Call Distributor |
| ACDS | Active Clock Distribution System |
| ACE | Advanced Components and Equipment |
| ACFC | Analog Color Field Computer |
| ACFZ | Acrylic Case For Zune |
| ACIP | ATM (Asynchronous Transmission Mode) Cable Interface Processor |
| ACIS | Advanced CCD Imaging Spectrometer |
| ACLT | Accelerated Cable Life Test |
| ACM | Association for Computing Machinery |
| ACM | Audio CODEC (COder-DECoder) Module |
| ACO | Automatic Cut Off |
| ACP | Administration Control Panel |