Eirenaios

Eirenaios is a Greek given name derived from the word eirene, meaning peace. In Greek, it is Ειρηναῖος; in Latinized form it is Irenaeus. The name has ancient roots and remains in use in Greek-speaking communities.

The most prominent bearer in early Christian literature is Irenaeus of Lyons (Greek: Ειρηναῖος ὁ Λυώνιος), an influential bishop of Lyon active in the late 2nd century CE. He is best known for his work Against Heresies, where he argued for the unity of the church, the authority of apostolic tradition, and the divinely given rule of faith against Gnostic systems.

Beyond him, the name Eirenaios appears for various other historical figures in Greek and Byzantine sources, and it continues to be used as a given name in modern Greece and other Greek-speaking communities. In scholarly contexts the form Irenaeus is often used for the classical figure, while Eirenaios/Hellenized spellings persist in Greek texts.

The name thus reflects a linguistic lineage from ancient Greek to Christian usage, carrying connotations of peace and fidelity to tradition.