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uno (Cardinal Number) "one"

10th cent. From Latin unus 'id.' Old Latin oino, accusative singular masculine of *oinos. From Proto-Italic *oino- 'id.' From late Proto-Indo-European *Hoi̯-no- 'id.' The first element *Hoi̯- is possibly from Proto-Indo-European *h1ei̯- "this/that."

Romance: Western Vulgar Latin: Asturian unu, Portuguese um, Galician un, Catalan un, French un, Italian uno ; Eastern Vulgar Latin: Aromanian un, Romanian unu ; Sardinian: unu

Indo-European: Celtic: Old Irish óen "," Middle Welsh un 'id.,' Old Breton un 'id.,' Cornish un 'id.;' Germanic: Gothic ains "one," Old Norse einn "," Old High German ein 'id.,' Old Saxon ēn 'id.,' Old English ān 'id.' (English one); Balto-Slavic: Serbian Chuch Slavic inъ "someone," Russian inój "other," Czech jiný 'id.,' Polish inny 'id.,' Slovene in 'id.,' Old Prussian ainan "one," Lithuanian víenas 'id.,' Latvian viêns 'id.;' Hellenic: Ancient Greek οἴνη (oíne) "one (one dice);" Indo-Iranian: Sanskrit éka- "one," Avestan aēuua- 'id.'