What term is used to describe very dry skin?

The term that describes very dry skin is xerosis. Xerosis is a medical condition characterized by the absence of moisture in the skin, leading to a rough, scaly texture. It can occur due to various factors, including environmental influences (like cold weather or low humidity), excessive bathing, or underlying health conditions that affect skin hydration.

In contrast, dermatitis refers to inflammation of the skin, which may involve symptoms like redness, swelling, and sometimes dryness, but it is not exclusively associated with dryness. Rash generally describes an area of irritated or inflamed skin, which can result from many causes, including allergies, infections, or irritants, and does not specifically imply dryness. Eczema is a type of dermatitis that often includes dry skin as a symptom, but it encompasses a broader range of symptoms such as itching, redness, and inflammation. Therefore, xerosis is the most accurate term specifically for very dry skin.