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

They try to stay in touch with loved ones through phone calls and WhatsApp messages, but the secrecy around carrier movements means their communication with their families is sporadic and unpredictable.

From The Wall Street Journal

The animal may be capable, but unpredictable disruptions make the job much harder.

From Science Daily

Fruit flies appear after rainfall, but climate change is making that rainfall more unpredictable, so pests are appearing at different times of the year.

From BBC

It’s unpredictable, a rebuke this day, an embrace the next, all depending on the moment and the speaker.

From The Wall Street Journal

Moscow and Kyiv both fear that the unpredictable American leader could hurt them if he loses patience.

From The Wall Street Journal

Related Words

• erratic
• fickle
• uncertain
• unreliable
• unstable