Fixed in refers to being firmly entrenched in a particular position or situation. There are several synonyms that can be used to describe this state, including rooted, ingrained, entrenched, set, established, solidified, and immovable. These terms convey the idea of being stuck or unable to move, with a sense of permanence or stability. Whether used to describe a person's beliefs or a situation that has been ongoing for a long time, these synonyms capture the concept of something that is steadfast and unchanging. Overall, there are many different ways to express the idea of being fixed in, each with its own nuances and connotations.