The phrase "wall in" can have multiple synonyms depending on the context and meaning. When the phrase is used in the sense of enclosing an area, some of its synonyms include enclose, surround, fence in, hem in, and box in. When used in the context of trapping someone or making them feel stuck, some of its synonyms are confine, restrict, imprison, incarcerate, and detain. In the context of construction, "wall in" can be replaced by terms such as build a wall, erect a partition, or create a boundary. The appropriate synonym for "wall in" depends on the context and usage.