acid rain

noun

: rain that has increased acidity caused by environmental factors (such as atmospheric pollutants)

Examples of acid rain in a Sentence

trees damaged by acid rain
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Overnight, the smoke coiled upward and gave way to acid rain that stained the city black. Cora Engelbrecht, New Yorker, 20 Mar. 2026 Burning oil also forms compounds called polycyclic aromatic hydrocarbons, or PAHs, as well as toxic gases such as sulfur dioxide and nitrogen oxides, which cause acid rain, said Peter Adams, a civil and environmental engineering professor at Carnegie Mellon University. Tammy Webber, Los Angeles Times, 15 Mar. 2026 These fires result in incomplete combustion, releasing a toxic slurry of carbon monoxide, soot, sulfur, and nitrogen oxides that can form acid rain, along with metallic compounds and oil droplets. Mrigakshi Dixit, Interesting Engineering, 11 Mar. 2026 The fear of a refinery spewing sulfur-dioxide soot and unleashing acid rain, Yoder said, was enough to prompt the county health department to create a pollution-control office to enforce air-quality regulations and end the refinery plans. Jenny Staletovich, Miami Herald, 10 Mar. 2026 See All Example Sentences for acid rain

Word History

First Known Use

1845, in the meaning defined above

Time Traveler
The first known use of acid rain was in 1845

Browse Nearby Words

Cite this Entry

“Acid rain.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/acid%20rain. Accessed 30 Mar. 2026.

Kids Definition

acid rain

noun
: rain with increased acidity that is caused by environmental factors (as atmospheric pollutants)

Medical Definition

acid rain

noun
: acid precipitation especially in the form of rain

More from Merriam-Webster on acid rain

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

More from Merriam-Webster