A huge bowel movement big enough to practically make your plumbing or septic tank crash. It is the combination of the spanish words choca - which means "hit" or "crash" - and the word tanque - which means "tank." Pronounced "cho-cah-tohn-keh"
"After Thanksgiving Dinner, I had to go to the bathroom and drop a big ol' chocatanque."
"Dude took a chocatanque so big that they had to call Roto-Rooter to fix the plumbing."