It's important to note that "Aztec" is a term used by historians to refer to the Mexica people, who were the dominant group in the Aztec Empire. The term "Nahuatl" actually refers to a family of languages spoken by many different groups in Mesoamerica, not just the Mexica. However, the specific dialect of Nahuatl spoken by the Mexica is the most famous and well-documented.