This paper proposes a number of cross-linguistically applicable definitions of general terms that are useful for comparing reflexive constructions in the world's languages. The idea is that general theories of reflexive constructions must be based on broad cross-linguistic comparison, and that this must be based on clearly defined terms. At the same time, the paper offers a general overview of types of reflexive constructions and reflexivizers (reflexive pronouns and reflexive markers) in the world's languages.