An itch is that annoying tickling sensation on your skin that makes you want to scratch. You might get an itch from a mosquito bite, from dry skin, or from a wool sweater rubbing against your arm. The feeling can be mild and easy to ignore, or so intense that it's hard to think about anything else until you scratch it.

The word also describes a strong restless feeling or desire for something. When you have an itch to explore or an itch to try something new, you feel an urge that won't go away until you act on it. A musician might feel an itch to perform after weeks of just practicing. This kind of itch isn't physical, but it creates the same restless, nagging feeling as an actual itch on your skin.

When something itches, it causes that scratchy sensation. You might say “my nose itches” or “this tag is making my neck itch.” The word itchy describes something that causes itching, like an itchy sweater or an itchy poison ivy rash.