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oscuro (Adjective) "dark"
12th cent. From Latin obscurus 'id.' From ob(s) "toward" (see ob-) and a fossil *scurus or *curus meaning "darkened." From Proto-Italic *skoi-ro- or *koi-ro- 'id.' If indeed related to Greek, Celtic and Gothic cognates, then from Proto-Indo-European *skoh2-i̯-ro- 'id.' From a root *skeh2- "to cover."
Indo-European
Romance
Portuguese obscuro, Galician escuro, Catalan obscur, French obscur, Italian oscuro, Eastern Vulgar Latin: Aromanian scur, Romanian obscur, Sardinian iscuru
Germanic
Gothic skeirs "bright," Old Norse skírr 'id.'
Hellenic
Ancient Greek σκίρον (skíron) "shady," meaning uncertain