an impairment of health or a condition of abnormal functioning

a breakdown of a cell layer in the epidermis (as in pemphigus)

an abnormal but benign thickening of the prickle-cell layer of the skin (as in psoriasis)

a skin disease characterized by dark wartlike patches in the body folds; can be benign or malignant

an inflammatory disease involving the sebaceous glands of the skin; characterized by papules or pustules or comedones

disorder involving lesions or eruptions of the skin (in which there is usually no inflammation)