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viejo (Adjective, Noun) "old;" "old person"
11th cent. From Vulgar Latin veclus 'id.' From Latin vetulus "a little old." From vetus "old" and -ulus, a diminutive suffix (see -uelo). Vetus is from Proto-Italic *wetos "year." From Proto-Indo-European *u̯et-os 'id.' From the root *u̯et- 'id.'
Also the origin of the toponym Viejo, a town in Asturias.
Indo-European
Romance
Asturian vieyu, Portuguese velho, Galician vello, Catalan vell, French vieux, Italian vecchio, Aromanian veclju, Romanian vechi, Sardinian béciu
Italic
Umbrian vesune, name of a goddess (lit. "(woman of the) year"), Marsian uesune 'id.'
Albanian
Albanian vit "year"
Balto-Slavic
Old Church Slavonic vetъxъ "old," Russian vétxij 'id.,' Czech vetchý 'id.,' Bulgarian vétxi 'id.,' Lithuanian vẽtušas 'id.'
Hellenic
Ancient Greek ἔτος (étos) "year," dialects ϝέτος (wétos) "year," Mycenaean we-to 'id.'
Indo-Iranian
Sanskrit vatsará- "year"
Tyrsenian
Vesuna, goddess (borrowed from Italic)