Definition of black rain in English English dictionary
radioactive rain that fell on Hiroshima and Nagasaki following the atomic bombings of 19451996, Ōe, Kenzaburō, Hiroshima Notes (in English, translated from Japanese), Grove Press, 0802134645, page 192:
rain contaminated by fungi spores, soot, or other particulate matter1902, The New International Encyclopædia (in English), Dodd, Mead and Company, page 81: