IXTHYS

IXTHYS. A Greek acronym signifying “Jesus (Iesous) Christ (Xristos) Son of God (Theou Yios), Savior (Soter),” also spelling out the Greek word for “fish.” Christians, obliged to keep under cover during the preconversion Roman Empire (q.v.), would thus use the iconography of a fish for the purpose of declaring themselves to other believers.