ἔκδικος ékdikos

Meaning

carrying justice out, i.e. a punisher

In the King James Version: a (re-)venger

Derivation: from G1537 (ἐκ) and G1349 (δίκη);

Where it is used

• Romans 13:4 For he is God’s servant for your good. But if you do wrong, be afraid, for he does not carry the sword in vain. He is God’s servant, an agent of retribution to the wrongdoer.
• 1 Thessalonians 4:6 and no one should ever violate or exploit his brother in this regard, because the Lord will avenge all such acts, as we have already told you and solemnly warned you.