Chaos
Chaos : A term that had been used since antiquity to describe various forms of randomness. It is now a commonly accepted technical term referring to the irregular, unpredictable, and apparently random behavior of deterministic dynamic systems. Solutions to deterministic equations are chaotic if adjacent solutions diverge exponentially in phase space. See: Socolar (2002) or Wolfram (2002) for a general discussion of chaos, and Turcotte and Malamud (2002) for an application in seismology