This form of dancing, if you can call it that, results from persons consuming too much alcohol, which somehow fuels their confidence in a non-existent ability to dance.
The drunken dance can be mistaken for someone going into convulsions or having an undiagnosed neurological disorder. It is often painful to watch, but the drunken dancers are convinced that they are performing on a professional level.
Chrissie got pretty wild at that bar last night.
Oh no, she wasn't drunken dancing again, was she?