Sight is the ability to see with your eyes. Of all your senses, sight gives you the most information about the world around you: the colors of a sunset, the words in a book, the expression on a friend's face. Your eyes work like cameras, capturing light and sending signals to your brain that turn into images you can understand.

Sight also means something you can see, especially something remarkable or unusual. The Grand Canyon is an amazing sight. A friend might arrive at school wearing a ridiculous Halloween costume and someone jokes, “Now that's a sight!” When you visit a new city, you might go sightseeing to view famous landmarks and interesting places.

The word appears in several useful expressions. When something disappears from view, it goes out of sight. Something obvious is in plain sight. When you understand something immediately without needing explanation, you grasp it at first sight. And the phrase sight unseen means accepting something without looking at it first, like buying a used bicycle sight unseen based only on the seller's description.

Sight can also mean the device on a weapon that helps you aim accurately. A rifle sight helps a hunter line up a target before shooting.