This name is not to be confused with Ποιμάνδρης (Poimandres), which is a name used as the title for the first chapter of the medieval literary work Corpus Hermeticum. That name is most likely a hellenization of the Egyptian theophoric name P-eime n-Re meaning "intelligence of Re" or "knowledge of Re", since it cannot be a genuine Greek given name because it doesn't follow the grammatical rules that all genuine Greek names do.
In Greek mythology, Poemander was the founder of the city of Tanagra.