Moisturize: To dampen; to replenish lost liquid; to add vapor; to humidify. "Moisturize" usually suggests that the thing receiving liquid is made slightly wet, but is not saturated.
Over-the-counter (OTC) skin lotions contain ingredients that moisturize dry skin, making it soft and supple but not wet. Humidifiers vaporize water to moisturize dry air.
The term "moist heat" is used to describe compresses or towels dampened with hot water and applied to the site of inflammation or pain to provide relief.
"Moisturize" is derived from the Old French word "moiste," meaning moldy. "Moiste" was derived from "mucidus," the Latin word for "moldy."