imperil

American  

[im-per-uhl] / ɪmˈpɛr əl /

verb (used with object)

imperiled, imperiling, imperilled, imperilling

1. to put in peril or danger; endanger.

   Synonyms:

   chance, hazard, jeopardize, risk

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imperil British  

/ ɪmˈpɛrɪl /

verb

1. (tr) to place in danger or jeopardy; endanger

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Other Word Forms

• imperilment noun

Etymology

Origin of imperil

First recorded in 1590–1600; im- ¹ + peril

Explanation

One thing can imperil another when it threatens to be harmful. For example, an approaching storm with hurricane-force winds might imperil the geraniums you just planted in your front yard. A city's budget cuts might imperil a school's ability to hire new teachers and buy supplies. The lack of money, in other words, is a threat to schools. Likewise, a factory's refusal to reduce its greenhouse gas emissions will imperil the air quality nearby — and ultimately, imperil the health of the whole planet. The word imperil comes from in and peril, meaning "danger."

Example Sentences

Microsoft on Tuesday warned a judge that the Pentagon blacklisting of Anthropic could hamper US warfighters and imperil the country's drive to lead in artificial intelligence.

From Barron's • Mar. 11, 2026

In the mid-19th century, do-gooders such as William Alcott and Sarah Josepha Hale began urging children be fed a bland diet, lest rich flavoring imperil their health and futures.

From The Wall Street Journal • Feb. 20, 2026

Stretching it out could give the U.S. time to act, but failing to eliminate key capabilities could imperil the invasion’s next steps.

From The Wall Street Journal • Dec. 7, 2025

These cuts will also imperil the health and well-being of the American people, making the country less prosperous and dynamic, both in the present and for future generations.

From Salon • Jun. 12, 2025

Altogether it is thought–though it is really only a guess, based on extrapolating from cratering rates on the Moon–that some two thousand asteroids big enough to imperil civilized existence regularly cross our orbit.

From "A Short History of Nearly Everything" by Bill Bryson

Related Words

• compromise
• endanger
• jeopardize
• menace