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

When variable interest rates make payments unpredictable HELOCs typically have variable interest rates, meaning borrowing costs can change over time. — Angelica Leicht, CBS News, 22 Oct. 2026

Adam has a vulnerability and warmth that immediately drew me to him, but there’s also something unpredictable underneath – a quiet strength that feels completely right for Hákon. — Georg Szalai, HollywoodReporter, 22 Oct. 2026

The Sissi combines rum, lime and chestnut honey, with notes of coffee and mint, for a tipple as intense, sweet and unpredictable as its namesake princess. — Jaclyn Degiorgio, Condé Nast Traveler, 22 Oct. 2026

Holy Cross and the Lower Ninth Ward that borders it are known for their quiet ambiance, grocery store deserts, and drawbridge access with unpredictable hours. — Nina Corcoran, Pitchfork, 21 Oct. 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