Stress may refer to: Mechanical Stress (mechanics), the average amount of force exerted per unit area Yield stress, the stress at which a material begins to deform plastically Compressive stress, the stress applied to materials resulting in their compaction Biological Stress (biological), physiological or psychological stress; some types include: Chronic stress, persistent stress which can lead to illness and mental disorder Eustress, positive stress that can lead to improved long-te… (More on Stress)