| 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. |
| yellow rain n. A powdery, poisonous, yellow substance reported as dropping from the air in southeast Asia and found to be the excrement of wild honeybees contaminated by a fungal toxin. |
yellow rain
airborne substance that was alleged to have been used in biological attacks in Southeast Asia from the mid-1970s to the mid-1980s.
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