κακόγλωσσος
From LSJ
αἰὲν ἀριστεύειν καὶ ὑπείροχον ἔμμεναι ἄλλων → always strive for excellence and prevail over others (Iliad 6.208, 11.784)
English (LSJ)
ον,
A ill-tongued, βοὴ κ. a cry of misery, E.Hec.661. II bringing evil [on oneself] by one's tongue, of Niobe, Call.Del.96.
German (Pape)
[Seite 1299] von böser, Unglück redender Zunge; βοή, Unglücksklagen, Eur. Hec. 661; Νιόβη, die zu ihrem Unglück gesprochen, Callim. Del. 96; Sp.