Lint is the fuzzy bits of fiber that come off fabric and collect in small clumps. If you've ever pulled clothes from the dryer and found them covered in gray fuzz, that's lint. It forms when tiny threads break loose from towels, cotton shirts, wool sweaters, and other fabrics as they rub together during washing and drying.

Dryers have lint traps (small screens that catch the fuzz) that need regular cleaning, or the dryer could overheat and become a fire hazard. You might also find lint in your pockets after carrying tissues, or in your belly button after wearing a new shirt.

The word can describe anything that looks like these fuzzy bits. Dust bunnies under the bed are partly made of lint. Some people use a lint roller (a sticky cylinder) to remove lint from dark clothing before heading out the door, since it shows up especially clearly on black pants or navy sweaters.