Rosacea (rose-) is a chronic skin disease that causes varying degrees of redness and swelling, primarily on the face, but also at times on the scalp, neck, ears, chest, and back. It is considered a vascular disorder (a disorder of the blood vessels).

The condition can develop over a long period of time and is more common in adults, particularly those with fair skin. More women get it than men, though in men the condition is often more pronounced. Severe, untreated rosacea can lead to a disfigurement of the nose called rhinophyma.