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dueño (Noun) (m. & f.) "owner;" (m.) "master;" (f.) "mistress," "lady"
11th cent. From Latin dominus 'id.' From Proto-Italic *domo-no- "(person) of the house." Derived from *domo- "house." From Proto-Indo-European *dōm 'id.,' a root noun.
Also the origin of the surnames Dueñas, Doña, Doñamayor, and Doñas.
Indo-European
Romance
Portuguese dono, Catalan don, French dom, Italian don, Aromanian domnu, Romanian domn
Indo-Iranian
Sanskrit dámūnas- "lord of the house"

Cf. Basque dono- "saint," "holy," found in toponyms (e.g., Donostia), and was borrowed from Vulgar Latin *domnus "lord." Thus, dono- entered Basque during Latin's evolution into the Romance languages.