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yugo m. (Noun) "yoke"
13th cent. Old Spanish yugo, iuuo. Borrowed from Latin iugum 'id.' From Proto-Italic *jugo- 'id.' From Proto-Indo-European *i̯ug-o- "yoke," but more literally "joined together." From the root *i̯eu̯g- "to yoke together."
Also the origin of the surname Yugo.
Variants
Almerían huvo, Old Spanish iuuo
Indo-European
Romance
Asturian xugu, Portuguese jugo, Galician xugo, Catalan jou, French joug, Italian giogo, Aromanian chubo, Romanian jug, Sardinian giú
Celtic
Old Irish cuing "yoke," Middle Welsh iou 'id.,' Middle Breton yeu 'id.,' Cornish ieu 'id.'
Germanic
Gothic juk "yoke," Old Norse ok 'id.,' Old High German joh 'id.,' Old Saxon juk 'id.,' Old English geoc 'id.' (English yoke)
Balto-Slavic
Old Church Slavonic igo "yoke," Russian ígo 'id.,' Czech jho 'id.,' Polish jugo 'id.,' Slovene igọ̑ 'id.,' Lithuanian jùngas 'id.,' Latvian jûgs 'id.'
Indo-Iranian
Sanskrit yúj- "ally," Young Avestan yuiiō- "yoke"

Myriad written attestation in Spanish and in Romance languages affirm that this is not a learned borrowing from Latin, yet Corominas (1991) notes that we should expect **jogo from iugum, and not yugo. Preservation of yu- could be from Leonese influence.

Old Spanish iuuo (early 13th cent.), however surprising, cannot be dismissed as a writing error: in the Almerían dialect we find a modern reflex in huvo. This must be a continuation of Vulgar Latin *iuum.

The ability to reconstruct a word for yoke in Proto-Indo-European proves that the ancient Indo-Europeans had draft animals used to pull wheeled carts.