The term "close in" can refer to various things such as proximity, confinement or conclusion. If you're looking for synonyms to use in your writing, alternatives for the word "close in" could include "nearby," "proximate," "enclosed," "confined," "restricted," or "encircled." Additionally, if you're using the term to mean "conclude" or "draw to a close," synonyms could be "terminate," "finish," "complete," or "end." By using synonyms, you can add more depth and variety to your writing and avoid overusing the same words. Practice using synonyms for "close in" to enhance your vocabulary and make your writing more impactful.