hysteresis /his′tərē″sis/ [Gk, hysterein, to be late] , 1. a lagging or slowing of one of two associated phenomena or a failure to act in unison. 2. the influence of the previous condition or treatment of the body on its subsequent response to a given force, as in the elastic property of a lung. At any given lung volume the elastic recoil pressure within the airways during expiration is less than that which exists at the same lung volume during inspiration.
