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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."
Romance: Western Vulgar Latin: Portuguese obscuro, Galician escuro, Catalan obscur, French obscur, Italian oscuro; Eastern Vulgar Latin: Aromanian scur, Romanian obscur; Sardinian: iscuru
Indo-European: Germanic: Gothic skeirs "bright," Old Norse skírr 'id.;' Hellenic: Ancient Greek σκίρον (skíron) "shady?"