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

“The U.S., we’ve been neighbors for years, and we’ve fought in wars together. But ultimately, things have become very unpredictable,” said Sasha Ivanov, a Canadian programmer from Calgary who developed the app.

From The Wall Street Journal

Last month, delivery workers in several Indian cities went on strike over falling incomes, unpredictable incentives and unsafe conditions.

From BBC

In Madeline Cash’s dark comedy, a married couple’s new arrangement has unpredictable effects on their three children.

From The Wall Street Journal

But Nighthand was unpredictable, and angered, and six feet ten inches tall, so he did not say it aloud.

From Literature

Arms-control advocates counter that such an approach risks triggering an unpredictable new arms race.

From The Wall Street Journal

Related Words

• erratic
• fickle
• uncertain
• unreliable
• unstable