τετραετοῦς τετραετής, four years old Morpho works with a static database. If you like, you can compare the output of Morpheus.Parsed as: masculine genitive singular feminine genitive singular neuter genitive singular of τετραετής Search the corpus for this form only: τετραετοῦς τετραετής Singular MasculineNeuter Nominative – – Genitive – – Dative – – Accusative τετραέτεα τετράετες Vocative – –