An eyelet is a small, round hole that's reinforced around the edges, usually found in fabric, leather, or other materials. If you look at your sneakers, you'll see eyelets where the shoelaces thread through. Each hole has a metal or plastic ring around it to keep the fabric from tearing when you pull the laces tight.

Eyelets appear in many places beyond shoes: in the holes of a three-ring binder, along the edge of a tarp where you'd tie it down, or in a belt where the prongs fasten. Sailors use eyelets in sails, and tailors put them in clothing for laces or drawstrings. The reinforced ring is what makes it an eyelet rather than just a hole. Without that protection, the material would eventually fray and rip from repeated use.