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

One of Europe's deadliest migration corridors, where unclaimed bodies often wash up on shore, the passage to Crete is fueled by wars and instability across Africa and is growing busier even as pressure eases on other Mediterranean routes. —Lefteris Pitarakis, Arkansas Online, 1 Mar. 2026

But the killing of Khamenei, who had ruled Iran for more than three decades, creates a leadership vacuum, increasing the risk of regional instability. —Jon Gambrell, Chicago Tribune, 1 Mar. 2026

Iran’s strikes sent Gulf stock markets plummeting, while analysts forecasted oil prices would spike amid regional instability, Semafor’s Matthew Martin reported. —Mohammed Sergie, semafor.com, 1 Mar. 2026

And that really augurs the potential for severe and prolonged enduring instability in this region. —ABC News, 1 Mar. 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