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

The Met Office has issued a yellow rain warning for south-west England, valid between 18:00 Monday and 21:00 Tuesday with 10-20mm falling widely and up to 50mm over Dartmoor.

From BBC • Feb. 2, 2026

A yellow rain warning is also 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

A yellow rain warning, indicating a risk of flooding, is also in place in parts of the western UK.

From BBC • Dec. 6, 2024

I could see Penny, still in her little yellow duck pajamas and now a yellow rain hat, standing behind him.

From "Out of My Mind" by Sharon M. Draper