unpredictability
n. uncountable B2 Upper Intermediate US //ˌənpɹəˌdɪktəˈbɪɫɪti// UK //ʌnpɹɪdˌɪktəbˈɪlɪti// un·pre·dictabil·i·ty
n. the quality of being hard to guess or plan for. You use this when something changes suddenly and you cannot know what will happen next.
n. the quality of being difficult to foresee or anticipate; a lack of consistency or regularity in behavior or outcomes.
The weather in this region is famous for its unpredictability.
The stock market's unpredictability makes it a risky choice for people who need their money to stay safe.
While the scientist's theory was elegant, its failure to account for the unpredictability of human behavior led to a complete overhaul of the research model.
From un- + predictability.