Assuetude is a relatively uncommon word that refers to a habitual or accustomed behavior. Although it may not be a commonly used term, there are several synonyms that can be used in its place. Some of these synonyms include routine, custom, habit, tradition, convention, familiarity, and practice. Each of these words captures the idea of a behavior that is frequent, regular, and familiar to the individual. Whether you are discussing someone's personal habits or describing a larger cultural practice, these synonyms for assuetude provide a nuanced and detailed way to describe how people behave and interact with the world around them.