Yours, Etc.: Origins and Uses of 8 Sign-Offs
early 15c., from Middle French continuité, from Latin continuitatem (nominative continuitas), from continuus (see continue). Cinematographic sense is recorded from 1921, American English.
continuity con·ti·nu·i·ty (kŏn'tə-nōō'ĭ-tē, -nyōō'-)n.
The state or quality of being continuous.
An uninterrupted succession or flow; a coherent whole.