Hydrator
A humectant that attracts and holds water in the skin. Found naturally in the body; used topically at various weights.
Draws moisture in for a plump, comfortable feel and can soften the look of fine dehydration lines.
Serums, essences, sheet masks, moisturizers. Common at 0.1–2%.
Dehydrated skin of any type, including oily skin that feels tight.
In very dry climates, apply to damp skin and seal with a moisturizer so it doesn't pull moisture from deeper layers.
It hydrates (water content) but does not moisturize (oil/occlusion) on its own — pair with an emollient or occlusive.
Layer well under most products; apply before heavier creams and oils.
Frame it as a 'drink of water' for the skin — best on damp skin, sealed in by moisturizer.