In Greek mythology, Syllis (Ancient Greek: Συλλίδος) was a Sicyonian nymph who mothered Zeuxippus by Apollo. Her son succeeded Phaestus as the king of Sicyon when the latter migrated to Crete.^[1] In some accounts, the mother of Zeuxippus was called Hyllis, daughter of Hyllus and Iole.^[2]