καταδῐαιτάω · katadiaitaō — LSJ
decide as arbitrator against, give judgement against, give judgement, against, condemn, to be the cause of an arbitration being given against
decide as arbitrator against one, give judgement against, opp. ἀποδ-, ὁ διαιτητὴς οὐ κατεδιῄτα, ἀλλʼ ἀπιὼν ᾤχετο ἀποδιαιτήσας τούτου τὴν δίαιταν D. 49.19, cf. 21.84; οἷός τʼ ἦν πείθειν αὐτόν, ἣν κατεδεδιῃτήκει, ταύτην ἀποδεδιῃτημένην ἀποφαίνειν ib. 85; ἔρημον κ. τινὸς [δίκην] give judgement in default against one, Id. 21.92, cf. 40.17, Luc. Pr.Im. 15: metaph., condemn, c. gen., Alciphr. 1.31:—Med., καταδιαιτᾶσθαι δίαιτάν τινος to be the cause of an arbitration being given against one, Lys. 25.16