Macule - Circumscribed area of change in normal skin color with no skin elevation

Papule - Solid, raised lesion up to 0.5 cm in diameter; variable color

Nodule - Similar to papule but located deeper in the dermis and subcutaneous tissue; more than 0.5 cm in diameter

Plaque - Circumscribed elevation of skin more than 0.5 cm in diameter; often a confluence of papules

Pustule - Circumscribed area of skin containing purulent fluid

Vesicle - Circumscribed, elevated, fluid-filled lesion up to 0.5 cm in diameter

Bulla - Circumscribed, elevated, fluid-filled lesion greater than 0.5 cm in diameter

Petechiae - Small red or brown macules up to 0.5 cm in diameter that do not blanch with pressure

Purpura - Circumscribed petechiae more than 0.5 cm in diameter

Scales - Excess dead epidermal cells produced by abnormal keratinization; scaling in sheets is desquamation

Erosion - Focal loss of epidermis; heals without scarring

Ulcer - Focal loss of epidermis and dermis; heals with scar

Excoriation - Linear or angular erosions due to scratching

Crust - A collection of dried serum and cellular debris

Lichenification - Area of thickened epidermis that results from habitual rubbing

Atrophy - A depression in the skin resulting from thinning of the epidermis or dermis