Kyriotis (κυριότης) refers to lordship, sovereign authority, or dominion — and also to 'Dominions' as a category of angelic beings in Paul's cosmic hierarchy. From kurios (Lord), it is the abstract noun for the condition or exercise of lordship. It appears in Ephesians 1:21, Colossians 1:16, 2 Peter 2:10, and Jude 8 — in both cosmic and ethical contexts.
In Colossians 1:16, Christ is said to have created all things, including kyriotetes (dominions) — angelic powers are among His creations, subordinate to Him. Ephesians 1:21 places Him 'far above all... dominion, power, and every name.' The practical significance: no spiritual power, however exalted, stands over Christ. 2 Peter 2:10 and Jude 8 warn against those who 'reject authority (kyriotis)' — slander the celestial beings, showing lawlessness of the deepest kind.
Paul's cosmic Christology (Colossians 1, Ephesians 1) is a direct confrontation with any system that places spiritual powers above or alongside Christ. There are kyriotetes — yes, real angelic authorities. But Christ created them all, and His resurrection places Him above them all. No power in the universe stands over the believer's Lord. This is the theological foundation of Christian courage.