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curso m. (Noun) "course"

13th cent. Old Spanish corso, curso. A learned borrowing from Latin cursus "way," "course." The native word in Spanish is coso (1).

Romance: Western Vulgar Latin: Portuguese corso, cosso, French cours, Italian corso; Eastern Vulgar Latin: Romanian curs

Indo-European: Celtic: Gaulish Καρρόδουνον (karródounon) "wagontown," Old Irish carr, Middle Welsh carr, Old Breton carr, Cornish car; Germanic: Faroese hurra "to take off," Norwegian hurre "to turn," Middle High German hurren "to dash," English to hurry
cutir (Verb) "to strike"

From Latin quatere 'id.' From Proto-Italic *kwat-i- 'id.' From Proto-Indo-European *(s)ku̯ot-i̯- 'id.'

Indo-European: Germanic: Old Saxon skuddian "to shake," Old High German scutten 'id.,' English to shudder; Balto-Slavic: Lithuanian kùsti "to recover"
cuyo (Personal Pronoun) "whose"

13th cent. From Latin cuius "of whom" (Archaic Latin quoius), genitive of qui "who" (see (see quién and (see qué). From Proto-Italic *kwojjei 'id.' From a pre-form *kwosi̯os, a pre-Italic reformation of the old Proto-Indo-European genitive *kwoso 'id.'

Romance: Western Vulgar Latin: Portuguese cujo, Italian cui

Italic: Oscan púiiu, Paleo-Umbrian poíeí? (meaning unclear)

Indo-European: Hellenic: Ancient Greek ποῖος (poîos) "what kind"