The DTS name is an acronym for "DeVille Touring Sedan". The name was shortened when the DeVille underwent some revisions in style and power. The DTS debuted in 1995.
The "DTS" as in Cadillac DTS stands for DeVille Touring Sedan. The Cadillac DTS replaced the Cadillac DeVille. The Cadillac DTS was first produced in 2005.