- plural form of do
- (computing) Acronym of Disk Operating System, especially: a collective term for disk(ette)-based operating systems (PC-DOS, MS-DOS, DR-DOS, Novell DOS, FreeDOS) available for IBM and IBM-compatible personal computers from the early 1980's, although the term was used before then to refer to any disk-based operating system (such as the Data General "Diskette Operating System" for their minicomputers, or for the TRS-80 DOS used when the computer was upgraded from cassette data storage to diskette).
- (US) Initialism of Department of State
dos (plural doses)
- (military) Initialism of date of service
- (military) Initialism of date of separation
- (sciences) Initialism of density of states
- (education) Initialism of director of studies
- (computing, Internet) Denial of Service
- (teaching) Director of Studies; someone in charge of the academic side of a school including training teachers and deciding course materials.