Ζῆν οὐκ ἄξιος, ὅτῳ μηδὲ εἷς ἐστι χρηστὸς φίλος → Life is not worth living if you do not have at least one friend.
λύρα, λύρη, πηκτίς, πακτίς, χέλυς, χελώνη