(1) (Desktop As A Service) A thin client architecture that is delivered from a cloud service provider rather than from inhouse servers. The users' computers function like remote input/output terminals to the servers in the datacenter. See desktop virtualization, cloud computing and XaaS.
(2) (Data As A Service) Data services over the Internet, such as e-mail verification and address verification.
(3) (Data As A Service) A central repository for enterprise data. The "service" aspect means that the data are available to all users and are not tied to the format of one type of application.