The headword, presumably extracted from the quotation given, is genitive singular of the feminine noun do/ca (delta 1362, delta 1663, delta 1364, delta 1365, delta 1367, delta 1368).
[1] This quotation was left unidentified by Adler, but latterly Favuzzi [see under alpha 1596] 199-200 finds vocabulary-based grounds for attributing it to Dionysius of Halicarnassus. As regards the 'Fabius' in it, Favuzzi notes that the only Fabius mentioned otherwise in DH is Q. Fabius Maximus Rullianus (phi 3: cos. 322, 310, 308, 297, 295), but of course there are other possibilities. For me/ga e)kboh/santes cf. Josephus, Antiquities of the Jews 8.219.