| Acronym | Definition |
|---|
| DAO | Data Access Objects (Microsoft) |
| DAO | Double Action Only (handguns) |
| DAO | Dragon Age: Origins (video game) |
| DAO | Disk-At-Once (CD creation) |
| DAO | Dessin Assisté par Ordinateur (French: computer assisted design) |
| DAO | Data Assimilation Office |
| DAO | District Attorney's Office |
| DAO | Defense Attache Office |
| DAO | Departmental Administrative Order |
| DAO | Digital Asset Optimization (file indexing) |
| DAO | Dynamics of Atmospheres and Oceans |
| DAO | Design Approval Organization (Transport Canada) |
| DAO | Division Ammunition Officer |
| DAO | Defense Accounting Office |
| DAO | District Adjudications Officer |
| DAO | Defence Acquisition Organisation (Australia) |
| DAO | Duly Authorized Officer (mental health; New Zealand) |
| DAO | De-Asphalted Oil (refinery) |
| DAO | defense attaché officer (US DoD) |
| DAO | Department/Agency/Organization |
| DAO | Development & Ability Organization (Afghanistan) |
| DAO | District Adjudication Officers (US Immigration and Naturalization Service) |
| DAO | Division Aviation Officer |
| DAO | Defense Agency Operations |
| DAO | Data Analysis Office |
| DAO | Dial Address Outgoing |
| DAO | Disbursing Accounting Officer |
| DAO | Dayton Area Office (Los Alamos National Laboratory) |
| DAO | Days After Option (defense contracting) |
| DAO | Division Air Officer |
| DAO | Document Advisor Office |
| DAO | Director, Air Operations |
| DAO | Department of Army Organization |
| DAO | Dual Action Only (firearms) |
| DAO | Deskiñ d'An Oadourien (French teaching organization) |