The tendency of your brain to repeat the same word, name or lyric over and over in your head, for no reason. Usually happens in the morning when you're taking a shower or prior to first coffee, but can happen anytime. With music lyrics, often you don't even have the correct words. Sort of like an internal Tourettes Syndrome.
"I've got wicked brain drip with that damn Coldplay line about "are we human.' I hate that song!"
I had brain drip with the name "Dumbledorf" for my whole shower.