Back to back.

A move in square dancing in which two dancers face each other, then step forward and left until they have right shoulders adjacent, then move to a position where they are back to back, then move to have left shoulders adjacent, then return to facing each other.

plural of do do

(military) Initialism of date of service. / (military) Initialism of date of separation. / (computing, Internet) Initialism of denial of service. / (sciences) Initialism of density of states.

(computing, historical) Acronym of Disk Operating System, a family of disk-based operating systems. / (US) Initialism of Department of State.

(music) plural of do

plural of do

plural of to-do

(computing, Internet) A denial-of-service attack.

(teaching) Director of Studies; someone in charge of the academic side of a school including training teachers and deciding course materials.