| Abbreviation | Definition |
|---|---|
| µL | Microliter |
| 252 | Quarter measurement of a kilogram |
| A | Acre |
| A | Ampere |
| A | Angstrom |
| A/H | Ampere/Hour |
| ABR | Average Bit Rate |
| AC | Acre |
| ac. | acre |
| ACF | Actual Cubic Feet |
| ACFH | Actual Cubic Feet per Hour |
| ACFM | Actual Cubic Feet per Minute |
| ACMH | Actual Cubic Meters per Hour |
| ACP | Average Contribution Percent |
| ACPF | Average Cycle Per Fragment |
| ACPH | Air changes per hour |
| ADMT | Air Dried Metric Tonne |
| ADT | Average Daily Trips |
| AEM | All Equal Metric |
| AFT | Accelerated Failure Timeamp |