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
• changeful
• unstable

Examples of unpredictable in a Sentence

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

Recent Examples on the Web

One of the themes that emerged from my research is that disruptive change is predictably unpredictable. —Scott D. Anthony, Fortune, 29 Nov. 2025

Hanes Knit Full-Zip Hoodie Autumnal weather is notoriously unpredictable, and this zip-up hoodie will have your back, figuratively and literally, no matter what’s happening outside. —Nicol Natale, PEOPLE, 29 Nov. 2025

Something unpredictable on the homefront might take place – shortages, delays, breakages, even accidents. —Georgia Nicols, Denver Post, 27 Nov. 2025

The world is too complex and unpredictable—every object, surface, and motion adds new edge cases. —Jijo Malayil, Interesting Engineering, 27 Nov. 2025

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