- DOS (Disk Operating System)
- DOS/VS (Disk Operating System / Virtual Storage)
- DOS/VSE (Disk Operating System / Virtual Storage Extended)
- DOT (Department of Transportation)
- DOTA (short-form for DEFENSE OF THE ANCIENTS a popular online epic game)
- DOTC (Dakota Ojibway Tribal Council)
- DotD (Deal of the Day (marketing gimmick))
- DoTE (Department of Technical Education)
- DOTEO (Department of Transportation Emergency Organization)
- DOTLMS (Doctrine, Organizations, Training, Leader Development, Materiel, and Soldiers)
- DOTMLFP (doctrine, organization, training, maintenance, leadership, personnel, and facilities)
- DOTMLPF (Doctrine, Organization, Training, Materiel, Leadership, Personnel, and Facilities (mnemonic))
- DOTS (Digital-Optical Technology System)
- DOTSP (Doctrinal and Organizational Test Support Package)
- DOTT (The Domestication Of Thunnus Thynnus)
- DOU (Dourados Airport)
- Double Dip (Term used when in a dual status and receiving income from two sources (e.g. Military Technician on civilian leave and orders))
- DOV (Dover Air Force Base)
- DOVE (Defenders of the Ouse Valley and Estuary)