As a noun, rain is water that falls from clouds in drops. As a verb, it means for this water to fall from the sky.
It comes from Old English “regn” or “ren,” from Proto-Germanic “*regna-,” all meaning “rain.” It is one of the very old, basic weather words in English.
“Rain” is so old that its relatives appear in many Germanic languages, like German “Regen” and Dutch “regen.” This word has been spoken, in one form or another, by people watching the sky for thousands of years before weather apps existed.
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