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

More rain is expected to move in from the south during midweek and the Met Office has issued a yellow rain warning for southern England valid from 06:00 Wednesday until 08:00 Thursday.

From BBC • Feb. 18, 2026

One hundred areas of the UK face flooding as heavy downpours drench parts of the country, while the Met Office has issued yellow rain warnings for some areas.

From BBC • Feb. 10, 2026

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 in place from 12:00 GMT on Monday to 09:00 on Tuesday.

From BBC • Jan. 31, 2026

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