There are several synonyms for the term "Big Mac Index," which is an economic indicator used to compare the purchasing power of different currencies. One such synonym is "Burger King Index," which is a similar methodology but uses the price of a Whopper sandwich instead of a Big Mac. Another term that is sometimes used is "McDonald's Index," which is a more general term that refers to using the prices of McDonald's menu items as a way to gauge comparative price levels in different countries. Other common synonyms for the Big Mac Index include "Burgernomics" and "fast food index." Regardless of the term used, the index remains a useful tool for economists and investors seeking to understand international currency trends.