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

During this time of political instability the government ordered too few vaccine doses. — Kathryn H. Jacobsen, The Conversation, 21 Aug. 2026

Rather than wait on a turbulent regulatory environment that included FDA layoffs and bureaucratic instability, Nathan ran clinical and regulatory de-risking simultaneously. — Geri Stengel, Forbes.com, 21 Aug. 2026

None of the works address the recent bombardments directly, although the precarious context of ongoing threat, instability and struggle can be felt in almost all of them. — Los Angeles Times, 20 Aug. 2026

But instability isn't the only headwind stocks are facing, especially as the calendar turns toward the midterms. — Sarah Min, CNBC, 20 Aug. 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