(idiomatic) To rain heavily

Rain which is unusually acidic (pH of less than the natural range of 5 to 6); caused mainly by atmospheric pollution with sulphur dioxide, carbon dioxide and nitrogen compounds.

(meteorology) An area of diminished precipitation on the lee side of mountains.

A man who is believed to have power to control the rain. / A spirit of the rain.

(derogatory) An autistic, or mentally and/or socially impaired person. / (derogatory) A non-autistic or impaired person whose mannerisms are similar to such people. / (humorous) An expert at something.

Alternative spelling of sulfur rain

Rain that has a pale yellow colour caused by impurities picked up by the falling raindrops.

The interruption of an outdoor event because of rain, with the expectation that it would continue later.

rain contaminated by fungi spores, soot, or other particulate matter / radioactive rain that fell on Hiroshima following the atomic bombing of 1945

The first rainfall of a season, at the start of spring in cold climates or the end of summer in hot, dry climates.