Settled down is a common phrase used to describe a person who has become comfortable in a new place or situation. However, there are many synonyms that can be used in its place, giving writers a range of alternatives to choose from. Some options include established, situated, situated oneself, taken root, rooted oneself, acclimated, and adapted. Each of these synonyms implies a sense of stability and comfort, but with slightly different connotations. For example, established suggests a more formal sense of stability and routine, while acclimated implies a gradual process of adapting to a new environment. Regardless of the synonym chosen, using alternatives to settled down can add variety and interest to writing.