iudicium

Iudicium, iudicii is a second declension neuter built on iudex, iudicis, and behind that on ius plus dico: the speaking of the law. Three senses overlap and the context has to sort them out - the court and its proceedings, the verdict handed down, and the private faculty of judgement, as in meo iudicio, "in my opinion".

The genitive singular has two i's, iudicii, though verse and later manuscripts often contract it to iudici, which then looks exactly like the dative of iudex. Watch for that. In this corpus the eschatological use dominates: dies iudicii, the Day of Judgement, and iudicium extremum, the Last Judgement. English judgement, judicial, judicious and prejudice all descend from the family.