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libro m. (Noun) "book"
12th cent. From Latin librum, accusative of liber "book," but originally "tree bark." From Proto-Italic *lufro- 'id.' From Proto-Indo-European *lu̯bh-ro- "leaf." From *leu̯bh- "to peel."
Indo-European
Celtic
Old Irish luib "herb," Middle Welsh luibh 'id.,' Old Breton -lub 'id.,' Cornish lowarth "garden"
Germanic
Gothic lubja-leis "witchcraft," laub "leaf," Old Norse lýf "medicinal herbs," lauf "leaf," Old High German loub "leaf," Old Saxon lōf 'id.,' Old English lēaf (English leaf), lybb "poison"
Albanian
Albanian labë "rind"
Balto-Slavic
Russian lob "forehead," Czech leb "skull," Old Prussian lubbo "plank," Lithuanian lubà 'id.,' Latvian luba 'id.'
Basque
Basque liburu "book," borrowed from from Latin