Gristle is the tough, chewy tissue you sometimes find in meat, especially near bones or joints. It's technically cartilage: the same flexible material that shapes your nose and ears. When you bite into a piece of chicken and hit something rubbery that won't break down no matter how much you chew, that's gristle.

Most people find gristle unpleasant to eat because it feels so different from regular meat. It doesn't have much flavor, and your teeth can't easily cut through it. At dinner, you might politely move a piece of gristle to the side of your plate after realizing you've been chewing the same bite for far too long.

The word can also describe anything tough and sinewy. A writer might describe a gristly piece of meat, or use “gristle” metaphorically to mean the tough, unglamorous parts of something. The actual work of building a successful business involves plenty of gristle: the boring, difficult tasks that aren't glamorous but still need doing.