At the beginning of Odyssey 18, we meet the interesting character of Iros, a public beggar. ‘Iros’ is not his actual name, but it is what people call him:
He had the name Arnaios, for thus the lady his mother
called him from birth, but all the young men used to call him Iros,
because he would run and give messages when anyone told him. (18.5-7 [Lattimore's tr.])
The nickname is obviously chosen because of its similarity to ‘Iris’, the (female) messenger of the gods, as LSJ points out, though no etymology is given (a possible etymology, however, is given for ‘Iris’). But interestingly, as LSJ also points out, the nickname passed into the language as a general term not for ‘messenger’ but for ‘beggar’. One reference the lexicon gives is to Libanius, Oratio 18.140:
(140.) Οὗτοι τοίνυν οἱ βασιλέως ὀφθαλμοὶ καὶ φά-σκοντες ἅπαντα εἰς φῶς ἄγειν καὶ ποιεῖν τοὺς πονη-ροὺς μετρίους τῷ μὴ ἐξεῖναι λανθάνειν πάσας ἀνίεσανεἰς πονηρίαν ὁδοὺς καὶ μόνον οὐκ ἐκήρυττον, ὡς ἀκίν-δυνα δράσουσιν. ὥσθ’ οἱ κωλυταὶ τῶν ἀδικημάτων (5)αὐτοὶ τοὺς ἀδικοῦντας ἔσωζον κυσὶν ἐοικότες συμ-πράττουσι τοῖς λύκοις. διὰ ταῦτα ἴσον ἦν θησαυρῷτε ἐντυχεῖν καὶ τούτων μετασχεῖν τῶν μετάλλων. ὁγὰρ ἥκων Ἶρος ἐν βραχεῖ χρόνῳ Καλλίας.
For an interesting article on Iros as a paradigm for the suitors, see the aptly titled ‘Odyssey 18: Iros as Paradigm for the Suitors’, by Daniel B. Levine (CJ 77  200-204).