A moisturizer is a cream, lotion, or ointment that you put on your skin to keep it from drying out. Your skin naturally has moisture in it, but things like cold weather, hot showers, swimming in chlorinated pools, or just being outside in the sun can make it dry and uncomfortable. Moisturizer helps replace that lost moisture and creates a protective layer to keep your skin soft and healthy.

You've probably used moisturizer without thinking much about it: sunscreen often contains moisturizer, and lip balm is basically moisturizer for your lips. People with dry skin might apply moisturizer to their hands after washing them or to their face before bed. Athletes sometimes use moisturizer on their skin after training or competing outdoors.

Different moisturizers work in different ways. Some create a barrier that traps water in your skin, while others actually add moisture. Dermatologists (doctors who specialize in skin) often recommend moisturizer for people with skin conditions like eczema, where the skin gets especially dry and itchy.

The verb form is moisturize, which means to apply moisturizer or add moisture to something. You might moisturize your hands after doing the dishes, or a baker might moisturize a cake by brushing it with syrup.