n. - The state or quality of being intense; intenseness; extreme degree; as, intensity of heat, cold, mental application, passion, etc.
n. - The amount or degree of energy with which a force operates or a cause acts; effectiveness, as estimated by results produced.
n. - The magnitude of a distributed force, as pressure, stress, weight, etc., per unit of surface, or of volume, as the case may be; as, the measure of the intensity of a total stress of forty pounds which is distributed uniformly over a surface of four square inches area is ten pounds per square inch.
n. - The degree or depth of shade in a picture.