Liniment is a special kind of medicine that people put on their skin when they have aches and pains. It's kind of like a cross between lotion and medicine. You know how sometimes your muscles or joints might hurt after playing a lot or running around too much? Well, grown-ups have that happen to them too, except for them it's called arthritis or other things.
So, when grown-ups' muscles or joints hurt, they might use liniment to help feel better. It's usually a liquid that they pour onto their hands or a piece of cloth, and then they rub it onto the sore spot. Liniment has some special ingredients that make skin feel cooler or warmer, which can help lessen the hurt feeling in the muscles or joints. Sometimes, liniment smells pretty strong, like peppermint or eucalyptus. It's okay, though, and it'll go away in a little bit.
Liniment can be really helpful for making grown-ups feel better when they're sore, but it's important to ask an adult or a doctor before using it because it can be harmful if they use too much or put it on the wrong places.