Dehydrated skin lacks water. It is worth making the distinction between dehydrated skin and dry skin, which lacks nourishment (lipids, essential fatty acids).
Dehydration can affect all skin types, including combination to oily skin. Dehydrated skin feels tight, tingles, lacks radiance and is uncomfortable. In worse cases, the skin can even peel. Insufficiently hydrated, the skin no longer fulfils its protective barrier function.