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duro (Adjective) "hard"
13th cent. From Latin durus 'id.' From Proto-Italic *dūro- 'id.' From Proto-Indo-European *du̯h2-ro- 'id.' From the root *du̯eh2- "to endure."
Also the origin of the surname Duro and its diminutive surname Durelo.
Indo-European
Romance
Portuguese duro, Galician duro, Catalan dur, French dur, Italian duro, Romanian dur, Sardinian duru
Hellenic
Ancient Greek δηρός (derós)
Armenian
Armenian erkar
Indo-Iranian
Sanskrit dūrá- "far," Avestan dūrāt̃ 'id.'