yellow rain

American  

noun

1. small, powdery yellow deposits containing the fungal toxin tricothecene, found on leaves and other surfaces in Southeast Asia and Afghanistan in the early 1980s and alleged by some to be a chemical weapon disseminated by air but claimed by others to be pollen-containing bee excrement contaminated by fungus.

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yellow rain British  

noun

1. a type of yellow precipitation described in parts of SE Asia and alleged by some to be evidence of chemical warfare using mycotoxins

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Etymology

Origin of yellow rain

First recorded in 1975–80

Example Sentences

A yellow rain warning is in place from 12:00 GMT on Monday to 09:00 on Tuesday.

From BBC • Jan. 31, 2026

With rainfall totals increasing in South Wales, an additional Met Office yellow rain warning has been issued for Wednesday 06:00 to 23:59 GMT.

From BBC • Nov. 11, 2025

Eastern counties have a yellow wind warning, and a yellow rain warning is in place across Northern Ireland.

From BBC • Oct. 3, 2025

Northern Ireland and parts of Scotland and north-west England also have a yellow rain warning in place.

From BBC • Oct. 3, 2025

Jenny and Abby slipped into their bright yellow rain slickers and flipped up the hoods.

From "Dog Squad" by Chris Grabenstein