Orithyia. In Greek mythology, Orithyia or Oreithyia was the name of the following women: Orithyia, one of the Nereids. Orithyia, a daughter of Cecrops, wife of Makednos and mother of Europus. Orithyia, a daughter of Erechtheus. Orithyia, a nymph, called by some the grandmother of Adonis.