'aztecan' originates from Spanish, specifically the word 'azteca', ultimately from Nahuatl 'Aztēcatl', where the element 'Aztlān' referred to the mythical homeland and roots like 'aztatl' related to 'heron' (thus 'people from Aztlán').

'aztecan' changed from Spanish 'azteca' and English 'Aztec' (borrowed from Spanish), which in turn derive from the Nahuatl 'Aztēcatl'; the English form 'aztecan' developed as an adjectival/noun derivative of 'Aztec'.

Initially it meant 'a person from Aztlán' or 'a member of the Aztēcatl people', but over time it broadened to mean 'relating to the Aztec civilization, people, culture, or languages.'