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débil (Adjective) "weak"
15th cent. A learned borrowing from Latin debilis 'id.,' replacing Old Spanish feble (itself borrowed from Old French). From Proto-Italic *dē-bel-i- "without strength." From *dē- "undoing of" (see de-) and *bel- "strength." From Proto-Indo-European *bel-o- 'id.,'
Indo-European
Romance
Asturian débil, Portuguese débil, Galician débil, Catalan dèbil, French débile, Italian debole, debile, Eastern Vuglar Latin Romanian debil, Sardinian débbile, débbili
Balto-Slavic
Old Church Slavonic boļii "bigger," Russian ból'šij 'id.' BCS bȍljī 'id.'
Hellenic
Ancient Greek βέλτατος (béltatos) "best"
Indo-Iranian
Sanskrit bála- "strength"