Not “Enlightenment”, but “Enlightenments”, plural. An ah-ha moment where one realizes something paradoxical, or ridiculous, or both, and suddenly gets freedom and peace (and, in my experience, a good laugh) about it.
The funny thing about the ones I’ve collected is that, until you “get” them–experience them as enlightenments–they seem like really bad news. A few years ago, I made a list of the ones of which I was aware–maybe half a dozen–and shared them with a friend. When I noticed the terrified look on her face, I realized how depressing it all sounded, and I was laughing about it.
“Are you… are you alright? You know you can call any time, any time at all, even in the middle of the night–” and I laughed. “No, no, this is good news, I promise!” and then proceeded like I was trying to explain a joke, with similar results.