Achy describes the feeling of having dull, persistent pain in your muscles or body. When you're achy, you don't have a sharp, sudden pain like stubbing your toe. Instead, you feel a tired, uncomfortable soreness that won't quite go away.

You might feel achy the day after playing hard at recess or trying a new sport, when your muscles are recovering from unusual effort. When you're coming down with the flu, you often feel achy all over, with a general soreness in your arms, legs, and back that makes you want to curl up under a blanket. Growing pains can make kids' legs feel achy at night.

The word captures that specific quality of discomfort that's more annoying than alarming. An achy feeling tells you your body is tired or fighting something off, but it's usually temporary. You might say “my shoulders feel really achy” after carrying a heavy backpack all day, or “I'm feeling kind of achy” when you're getting sick.

The related noun is ache, which can be a feeling (a dull ache in your back) or a verb (your feet ache after a long hike).