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vuestro (Possessive Pronoun) "your"
12th cent. From Latin vostrum, accusative of voster 'id.' From Proto-Italic *wos-tero- 'id.' From Proto-Indo-European *u̯s-tero- 'id.'
Indo-European
Romance
Asturian vuestru, Portuguese vosso, Galician voso, Catalan vostre, French votre, Italian vostro, Aromanian vostru, Romanian vostru, Sardinian bostru