# unpredictable

/ˌənpɹɪˈdɪktəbəɫ/ (US) · /ʌnpɹɪdˈɪktəbəl/ (UK)

Source: https://englishreference.com/word/unpredictable
Updated: 2026-06-20

## Senses

### 1. not able to be foreseen

adjective · CEFR B2

describing something that changes so much you cannot guess what will happen next.

For teachers: not able to be foreseen or known beforehand; lacking a predictable pattern or consistency.

- The weather in the mountains is unpredictable, so you should bring a rain jacket.
- The stock market remained highly unpredictable throughout the fiscal year, defying the projections of even the most seasoned financial analysts.

### 2. behaving unexpectedly

adjective · CEFR B2

describing a person who often changes their mood or actions without warning.

For teachers: behaving in a way that is not easily anticipated; often used to describe temperament or personality.

- He is a talented actor, but his unpredictable temper makes him difficult to work with.
- The director found the lead actor's unpredictable outbursts exhausting, as they frequently disrupted the filming schedule and lowered the crew's morale.

### 3. an unexpected thing

noun · CEFR C1 · Formal

a person or thing that you cannot predict.

For teachers: a person, thing, or event that is impossible to predict. Often used in the plural to describe general uncertainties.

- In politics, you must always be prepared for the unpredictable.
- The strategist argued that the success of the campaign depended on how well the team managed the various unpredictables of the local election cycle.

## Examples

- The weather in the mountains is very unpredictable.
- Investors are nervous because the stock market has been highly unpredictable lately.
- The protagonist's unpredictable behavior keeps the audience in a state of constant tension, as his motivations remain obscured until the final scene.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.