The liquid portion of diarehea. More specifically a very dark black liquid that squirts from the ass with great force. The excretion contains no solid pieces and is very running.
I ate some day old tacos and now I'm fixin' to brew some black tea.
when you shit in your partners mouth and tea bag her!
Joey: hey bob guess what!
Bob: what joey?!
Joey: i gave maria a black tea last night
Bob: your distgusting