slang Diarrhea, especially that which is contracted from food poisoning. Usually refers to tourists traveling in Mexico or South America who lack immunity to bacteria that can be transferred via food and local drinking water. Also known as "Montezuma's revenge." The best way to avoid the Aztec two-step is to drink bottled water.
Aztec two-step
n. diarrhea, specifically that contracted in Mexico or South America by tourists; Montezuma’s revenge. I was there for only two days before I was struck down with the Aztec two-step.