unpredictable

American  

[uhn-pri-dik-tuh-buhl] / ˌʌn prɪˈdɪk tə bəl /

adjective

1. not predictable; not to be foreseen or foretold.

   an unpredictable occurrence.

   Synonyms:

   uncertain, variable, fitful, erratic

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noun

1. something that is unpredictable.

   the unpredictables of life.

unpredictable British  

/ ˌʌnprɪˈdɪktəbəl /

adjective

1. not capable of being predicted; changeable

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Other Word Forms

• unpredictability noun
• unpredictableness noun
• unpredictably adverb

Etymology

Origin of unpredictable

First recorded in 1855–60; un- ¹ + predictable

Example Sentences

But in a busy lifestyle with unpredictable hours, sticking to this sort of meticulous plan will be challenging - and I'm doubtful of my ability to pull it off.

From BBC

Residents have been warned to avoid the exotic animals, as they could be "unpredictable or aggressive under stress".

From BBC

Gen Kainerugaba is known for being unpredictable and provocative, especially on social media.

From BBC

In Victoria, authorities on Thursday warned that a catastrophic fire danger rating means potential blazes can be "unpredictable and uncontrollable".

From BBC

While timing remains unpredictable, understanding what lies beneath the Earth's surface can significantly improve risk assessments.

From Science Daily

Related Words

• erratic
• fickle
• uncertain
• unreliable
• unstable