impredecible
/impɾedeˈθible/ · B2 · adj
unpredictable
🎲🌪️ im- (not) + predecible (predict-able) = cannot be predicted, like a dice roll
Spanish im- means not, and predecible comes from predecir, to foretell (pre- before + decir to say). So impredecible is not able to be said beforehand. Note: the standard Spanish form is impredecible, matching English unpredictable.