μελάμπυγος
From LSJ
Ἔοικα γοῦν τούτου γε σμικρῷ τινι αὐτῷ τούτῳ σοφώτερος εἶναι, ὅτι ἃ μὴ οἶδα οὐδὲ οἴομαι εἰδέναι → I seem, then, in just this little thing to be wiser than this man at any rate, that what I do not know I do not think I know either
English (LSJ)
ον,
A black-bottomed, considered a mark of manhood, Eub.61; a name of Heracles, μ. τοῖς ἐχθροῖς a very Heracles to them, Ar.Lys.802 (lyr.), cf. Hdt.7.216: prov., μή τευ μ. τύχης take care not to 'catch a Tartar', Archil.110. II of a kind of eagle, v. πύγαργος.
German (Pape)
[Seite 118] mit schwarzem, schwarzbehaartem Hintern, was als Zeichen besonderer Mannhaftigkeit galt, ἐχθροῖς, Ar. Lys. 802. Vgl. Hesych. u. λευκόπυγος.