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

Coppola’s film put Fanning on the map, and she’s been turning in extremely varied and delightfully unpredictable performances in movies and television ever since.

From Salon

Its chemical behavior can be unpredictable, which has restricted its broader adoption.

From Science Daily

“Our only forecast can be for more disruptive events, at unpredictable times,” making for continued uncertainty for economists, investors, and traders.

From Barron's

“This might be his most unpredictable challenge yet,” it said while promoting the event.

From The Wall Street Journal

Retirees, by contrast, tend to face larger spending shocks than workers, often driven by unpredictable costs such as healthcare.

From MarketWatch

Related Words

• erratic
• fickle
• uncertain
• unreliable
• unstable