| Abbreviation | Definition |
|---|---|
| DAA | Decimal Adjust after Addition |
| DAB | Delete All But |
| DAC | Declare Address Constant |
| DACF | District Assembly Common Fund |
| DAI | Do As Infinity |
| DAL | Download And Leave |
| DAS | Decimal Adjust after Subtraction |
| DB | Define Byte |
| DBCS | Double Byte Character Set |
| DBMS | Direct Binary Machine Sort |
| DBZ | Divide By Zero |
| DC | Declare Constant |
| DC | Define Constant |
| DCOT | Double precision trigonometric COTangent |
| DCR | Define Constant Reversed |
| DD | Duplicate Disk |
| DDI | Discard Digits Instruction |
| DDR | Destination Data Register |
| DDWB | Deposit Directly in Wastepaper Basket |
| DE | Delete Entity |