Omega (noun)

1. The last letter of the Greek alphabet (Ω, ω), used in mathematics, physics and chemistry to represent the end or last point of a series, or an infinite limit.
2. The last, final, or ultimate element or aspect of something.
3. The last, final, or ultimate thing or event.

Origin:

From ancient greek ὦ (ō), the last letter of the greek alphabet.

Examples:

1. The omega point is the theoretical maximum level of complexity and consciousness that the universe can reach.
2. The omega of this series is the last element in the set.
3. In the end, it was the omega of his career.
4. The omega of his life was the last breath he took.
5. The omega of the story was the final twist in the plot.