The Greek dikaiokrisia (G1341) is a compound of dikaios (righteous) and krisis (judgment). It refers to perfectly righteous, impartial, and just judgment — the kind that only God can render completely.
Dikaiokrisia in Romans 2:5 confronts human judgment that condemns others while practicing the same sins. God's righteous judgment is both a warning and a comfort: a warning because it is perfectly accurate (no self-deception will survive); a comfort because it is perfectly fair — no injustice will go unaddressed. For the believer, dikaiokrisia is satisfied by the cross — Christ absorbed the righteous judgment we deserved.