When you catch yourself or someone else singing or using a frase from one of Michael Jacksons songs or doing the moonwalk.
"I could hear my sis sing Billy Jean in the shower this morning. She suffers from Micheal Moments constantly."
"Don't blame it on the moonlight, don't blame it on the sunshine, blame it on the boogie..."
It is likely that you will have your own Michael moment after reading this.