Hysteresis, or more recently hysteresis, can be:
generally:
dependence of some system (also) on its states in the past, see hysteresis (property)
the phenomenon that the effect lags behind the cause
in electrical engineering: magnetic hysteresis for short
in energetics: the difference between supplied and returned strain energy, see hysteresis (energetics)
in metrology: the property that the output signal of a measuring instrument for a given input signal depends on the sequence of previous values of the input signal, see hysteresis (metrology)
in economics: the non-restoration of the original equilibrium after a certain disturbance in the economic process (especially the absence of a further decrease in unemployment after the end of a depression), see hysteresis (economics)
in biology: hysteresis of protoplasm for short (aging of bioplasm)
in chemistry: sec. solidification of colloids as a result of a decrease in their electric charge, and thus reduced hydration, see hysteresis (colloids)
in cardiology: a relative prolongation of the Q–T interval in the ECG during a sudden change in the heart's action, see hysteresis (ECG)