English reaches for rain through Germanic mist, its monosyllable barely changed in a thousand years. Spanish and Esperanto both drink from Latin's pluvia — one drifting into the inheritance, the other reaching for it by design. Chinese 雨 does not name rain so much as draw it: cloud above, four drops below, a diagram made in oracle-bone that predates Rome. What separates these words is not the phenomenon but the nature of memory — whether a civilization stumbled into its word or chose it.
The Proto-Germanic root *regną is well-attested; a deeper PIE source (*reg- 'moist, wet') is proposed in some reconstructions but the connection beyond Germanic is unconfirmed — English 'rain' may be of purely Germanic provenance.
Latin pl- regularly becomes ll- in Spanish (pluvia → lluvia, planus → llano). The related verb llover descends from Latin pluere by the same shift; both noun and verb thus preserve the Latin root transparently beneath the Castilian surface.
One of the oracle-bone script's most legible pictographs: a horizontal cloud beneath the vault of heaven, with four drops descending. The visual argument has remained decipherable across three millennia — rain rendered without recourse to a phoneme.
雨 is Kangxi radical #173 and anchors a family of weather characters: 雪 xuě (snow), 雷 léi (thunder), 霜 shuāng (frost), 露 lù (dew). The character functions as both noun (rain) and verb (to rain) depending on grammatical context.
Productive Esperanto derivations from the stem: pluvas (it rains — present-tense verbal suffix -as), pluvego (downpour — augmentative -eg-), pluveto (drizzle — diminutive -et-), pluvema (rainy, prone to rain — aptitudinal suffix -em-), pluvombrelo (rain umbrella — compound with ombrelo).
Rain falls on every language equally — only the words for it reveal which civilizations looked up at the sky and which looked back through time.