ἀρχαϊσμός
From LSJ
τὸ κακὸν δοκεῖν ποτ' ἐσθλὸν τῷδ' ἔμμεν' ὅτῳ φρένας θεὸς ἄγει πρὸς ἄταν → evil appears as good to him whose mind the god is leading to destruction (Sophocles, Antigone 622f.)
English (LSJ)
ὁ,
A old-world charm of style, D.H.Comp.22. 2 use of obsolete expressions, ἀ. οὗτος ῥημάτων Men.11 D., cf. Sch.E.Hipp. 23. 3 ancient custom, περὶ ἀρχαϊσμοῦ, title of work by Manetho, Porph.Abst.2.55.
German (Pape)
[Seite 364] ὁ, altväterisches Betragen, bes. Nachahmung einer Alterthümlichkeit. Bei den Gramm. veralteter Sprachgebrauch.