What is the name of the tool used for filing the side edges of nails?

The tool used for filing the side edges of nails is called a nail file. Nail files come in various shapes, sizes, and abrasiveness levels to suit different filing needs. They are specifically designed to shape and smooth the edges of nails, allowing for a clean and polished finish. The side edges of the nails can often be sharp or uneven, and using a nail file helps to create a more aesthetically pleasing shape and prevents snagging.

Other options, while related to nail care, serve different functions. A nail clipper is used for cutting nails rather than filing them, a cuticle pusher is designed to push back or remove cuticles, and a buffer block is used to smooth the surface of the nail and add shine, not specifically for filing the edges. Thus, the nail file is the correct tool for the specific purpose of filing the side edges of nails.