The term 'PART OF A CHIPOTLE ORDER' can be summarized as a taco, which is a four-letter word. Tacos are a traditional Mexican dish consisting of a corn or wheat tortilla filled with various ingredients such as meat, cheese, beans, lettuce, and salsa. They are often served with sides such as guacamole, sour cream, and pico de gallo. Chipotle is a popular fast-food chain that specializes in tacos and burritos. Customers can customize their orders by choosing from a variety of fillings, toppings, and sauces.