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infierno m. (Noun) "hell;" "inferno"
12th cent. From Latin infernus 'id.,' but originally "of the lower region," from inferus "low." From Proto-Italic *enþero- 'id.' From Proto-Indo-European *n̥dher-o- 'id.' From *n̥dhér- "under."
Indo-European
Romance
Asturian infiernu, Portuguese inferno, Galician inferno, Catalan infern, French enfer, Italian inferno, Romanian infern, Sardinian iferru
Italic
Faliscan ifra "beneath"
Celtic
Gaulish anderon "of the gods of the underworld"
Germanic
Gothic undar "under," Old Norse undir 'id.,' Old High German untar "below," Old Saxon undar "under," Old English under
Indo-Iranian
Sanskrit ádhara- "lower," Young Avestan aδara- 'id.'