Amatus /am-a-tus/ [3 sylls.] as a name for boys is of Latin derivation, and the meaning of Amatus is God's love.Amatus is a version of Amadeus (Latin). Amat is a common last name.matus is also an unusual surname for all people. (2000 U.S. Census). Below is a graphed comparison of the usage of the boy name Amatus and related names. Amado is the only prominent alternative form of Amatus (not ranked) .