Metropolitanizing refers to the process of urbanization or making an area more like a metropolitan city. Some synonyms for this word could include "urbanizing," "city-fying," or "cosmopolitanizing." Other options could include using more specific language to describe the process, such as "modernizing," "industrializing," or "commercializing." Each of these synonyms carries a slightly different connotation, so choosing the most appropriate word depends on the context. For example, if discussing the growth and development of a city, using "urbanizing" or "city-fying" might be the best choice, while discussing the influx of new businesses or industries might call for "commercializing" or "industrializing".