unpredictable

adjective

un·​pre·​dict·​able ˌən-pri-ˈdik-tə-bəl 

: not predictable: such as

a

: not able to be known or declared in advance

unpredictable weather

b

: tending to behave in ways that cannot be predicted

an unpredictable boss

unpredictably

ˌən-pri-ˈdik-tə-blē 

adverb

changes that occur unpredictably

unpredictability

ˌən-pri-ˌdik-tə-ˈbi-lə-tē 

noun

the unpredictability of the weather

Synonyms of unpredictable

• volatile
• unstable
• changeful

Examples of unpredictable in a Sentence

unpredictable spring weather that makes it really hard to know what to wear

Recent Examples on the Web

In another social media post, Kelsie Abrams, who has worked at the Burke as the fossil prep lab manager for the past eight years, shared more about the delicate — and sometimes unpredictable — process of preparing them. — Jordan Greene, PEOPLE, 24 Sep. 2026

But in an unpredictable turn of events, Jackson said an explosion from within the home threw him from the window onto the ground. — Los Angeles Times, 24 Sep. 2026

The new prices may also steer customers more toward bundles, which streaming service providers believe lead to fewer cancellations and help Disney manage the unpredictable ads market. — Scharon Harding, ArsTechnica, 23 Sep. 2026

The open Atlantic Ocean presents a different kind of extreme — relentless, unpredictable and constantly changing — and that is exactly where Canada Goose belongs. — Lisa Lockwood, Footwear News, 23 Sep. 2026

Word History

First Known Use

1840, in the meaning defined above

Rhymes for unpredictable

• indictable
• predictable

Kids Definition

unpredictable

adjective

un·​pre·​dict·​able

ˌən-pri-ˈdik-tə-bəl

: not predictable

unpredictability

-ˌdik-tə-ˈbil-ət-ē

noun

unpredictably

-ˈdik-tə-blē

adverb