To me enlightenment is a moment, but also an ongoing state of being "enlightened" - past that moment. Enlightenment to me is the moment knowledge turns into a realization. When information in our brain receives extensive context that changes not only our view of a specific situation, but the way we perceive ourselves and our existence from a broader perspective.
I think the word "enlightenment" describes the sensation of realization and full acceptance of something quite well. It's like a light turns on in one's mind, showing things that were previously hidden in the dark.