For this sense of the verb diw/kw see also delta 1229 (LSJ entry at web address 1). The present entry is prompted by Aristophanes, Ecclesiazusae 452 (web address 2). Chremes is reporting to Blepyrus the public speech made by a "good-looking young man" (427) who, as the audience knows, is Blepyrus' wife Praxagora. After the negative remarks she has expressed on the subject of Blepyrus himself, her praise of women is now mentioned: ou) sukofantei=n, ou) diw/kein, ou)de\ to\n dh/mon katalu/ein, a)lla\ polla\ ka)gaqa/; "they are not informers, they don't prosecute, they don't undermine the people, but [they do] many good things". [The scholia vetera here have the gloss ei)s a)gora\n fe/rein without a preceding lemma. According to Rutherford's edition of the scholia, the gloss is to be referred to 'some unknown variant' or else identified as a 'misplaced comment'; but this Suda shows that missing lemma is almost certain to have been diw/kein.]
[1] For the agora (in Athens and elsewhere) see the sequence of entries between alpha 299 and alpha 313. Its economic and commercial role as a marketplace is self-evident, but such idioms as ei)s a)gora\n e)mba/llein (Lycurgus, Against Leocrates 5) are also used in the sense of "being a citizen"; and in the present instance the use of diw/kein highlights the agora as a place of assemblies, public speeches, and -- in the jurycourts which clustered there -- litigation. The use of diw/kein in a law-related context is evident from the expression o( diw/kwn as "prosecutor/plaintiff" vs. o( feu/gwn as "defendant" (e.g. Herodotus 6.82; Aeschylus, Eumenides 583) and o( diwko/menos (Antiphon 2.1.5; Xenophon, Apology 21); cf. also diw/kein tina\ peri\ qana/tou Xenophon, Hellenica 7.3.6; turanni/dos Herodotus 6.104. *diw/kw is also used in the sense of avenging a murder (Euripides, Orestes 1534; Aristotle, Politics 1269a2); the idiom di/khn diw/kein is a synonym for pursuing one’s own right in a court (Demosthenes 54.41). Note also the verb diwka/qein.
[2] Although the verb proupofeu/gw occurs only here, there is no reason to reject it (with Bernhardy) as a verbum suspectum. As for the meaning, see Hesychius delta2042, who explains diw/kein as katalamba/nein feu/gonta.
[3] cf. Aristonicus in Schol. Homer, Iliad 8.439a "[*zeu=s ... a(/rma kai\ i(/ppous] *ou)/lumpon de\ di/wke": o(/ti kuri/ws diw/kein le/getai, o(/tan profeu/gh| tis, nu=n de\ e)pi\ tou= sunto/nws e)lau/nontos;"(Zeus) rapidly drove (his chariot and horses) up to Olympus" (web address 3).
[4] For the general meaning in Aristophanes cf. Knights 368: diw/comai/ se deili/as, "I will sue you for cowardice". Here the quotation stems from Acharnians 699 (web address 4, see schol. ad loc., where wordplay arises from the double meaning of the word diw/kein: in the parabasis, the choryphaeus is complaining that after having fought and pursued the enemy at Marathon, nu=n d' u(p' a)ndrw=n ponhrw=n sfo/dra diwko/meqa, ka)=|ta prosalisko/meqa, "[We were the pursuers], but now we are the aim of the lawsuits of wicked prosecutors; and then, we are falling in their hands". The whole passage is clearly a satire on the Athenians’ filodiki/a (Clouds 207-8, Peace 505, Knights 1317). The reader would have expected a contrasting word such feu/gomen, and the joke rests on the use of passive, as in the following prosalisko/meqa "we are caught" (but also "convicted"). For a parallel example see Knights 969 e)/xwn kata/paston kai\ stefa/nhn e)f' a(/rmatos xrusou= diw/ceis *Smiku/qhn, "wearing a purple robe and a crown, on a golden chariot, you will pursue Smicythes…(through the courts)!", where Demos is apparently promised a triumph, as the purple and the diadem show, but instead of luxuries a forensic fight turns out to await him (web address 5).