A divot is a little chunk of grass or turf that gets dug out of the ground. Playing golf creates many divots.
Have you ever seen a lawn that is perfectly maintained and smooth? That's a piece of ground without any divots. A divot is a little piece of the earth that flies up when something sharp hits it, like an animal's sharp hooves. The chunk of earth is a divot, and the cavity left behind is also called a divot. The cleats of football players and the powerful swings of golf players both result in divots.