This conditional particle introduces hypothetical situations, regularly followed by the subjunctive mood. Early Attic inscriptions preserve ἐάν, which contracts to ἤν and ἄν in various dialects. When combined with καί ('and'), it forms κἄν through crasis. In Hellenistic and later Greek, it also functions like ἄν after relative pronouns, creating constructions like ὃς ἐάν ('whosoever'). The particle signals possibility and contingency throughout New Testament Greek.