indeterministic

/ˌɪndɪˌtɜrmɪˈnɪstɪk/
adjective
  1. Not able to be predicted or determined exactly; involving randomness or chance.
    • In quantum physics, the behavior of particles is often indeterministic.
    • The weather is so complex that it remains indeterministic beyond a few days.
    • Some philosophers argue that human free will makes the future indeterministic.