instability

noun

in·​sta·​bil·​i·​ty ˌin(t)-stə-ˈbi-lə-tē 

: the quality or state of being unstable

especially : lack of emotional or mental stability

Synonyms of instability

• unsteadiness
• precariousness
• unstableness
• insecurity

Examples of instability in a Sentence

Investors are worried about the current instability of the stock market.

The patient has a history of emotional instability.

Recent Examples on the Web

The fuel can develop instabilities within thousandths of a second. — Aman Tripathi, Interesting Engineering, 3 Sep. 2026

Chinese leader Xi Jinping arrived in Egypt seeking to build closer ties with the key US ally as instability spreads across the Gulf. — semafor.com, 2 Sep. 2026

Rising global instability, with ongoing wars in Ukraine and Iran, haven’t helped, Brooks added. — Christopher Rugaber, Los Angeles Times, 2 Sep. 2026

Potamopyrgus antipodarum sits at the heart of that tension between instability and innovation. — Carrie Arnold contributing, Quanta Magazine, 2 Sep. 2026

Word History

First Known Use

15th century, in the meaning defined above

Rhymes for instability

• affability
• audibility
• bistability
• capability
• changeability
• contractility
• credibility
• culpability
• disability
• disutility
• durability
• fallibility

Kids Definition

instability

noun

in·​sta·​bil·​i·​ty ˌin(t)-stə-ˈbil-ət-ē 

: the quality or state of being unstable

Medical Definition

instability

noun

in·​sta·​bil·​i·​ty ˌin(t)-stə-ˈbil-ət-ē 

plural instabilities

: the quality or state of being unstable

especially : lack of emotional or mental stability