adjective 1.not predictable; not to be foreseen or foretold: an unpredictable occurrence.
noun 2.something that is unpredictable: the unpredictables of life.
Related forms un·pre·dict·a·bil·i·ty, un·pre·dict·a·ble·ness, noun
un·pre·dict·a·bly, adverb
Synonyms
1. erratic, fitful, variable, uncertain.