Anglicised form of Irish Seán, from Old French Jehan, from Latin Johannes, variant of Ioannes, from Koine Greek Ἰωάννης (Iōánnēs), from Hebrew יוֹחָנָן (Yōḥānān, literally “God is gracious”).
Doublet of John, Jack, Johan, Johann, Johannes, Jean, Ian, Evan, Ivan, Shaun, Shane, and Giovanni.