rain
/reɪn/·레인·noun
water falling from clouds
Old EnglishCEFR A1
Root
Proto-Germanic '*regnaz' (rain)
Proto-Germanic *regnaz → Old English regn → Modern rain. Sibling forms: German Regen, Dutch regen, Swedish regn. Latin used pluvia — a separate root (root of English pluvial).
In a word
Germanic *regnaz. Line up the sister languages — English rain · German Regen · Dutch regen · Swedish regn. Looking at the same rain, the Germanic branch calls it by almost the same sound. Latin used a different root, pluvia — source of the technical English pluvial (relating to rainfall). Over a single English syllable, almost-identical sounds from the Germanic family fall together.
Examples
It is raining outside.
The rain stopped at noon.
They got caught in the rain.
Related
rainyrainfallrainbowraindroprainstorm