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lado m. (Noun) "side"
13th cent. From Latin latus 'id.' From Proto-Italic *slāto- 'id.' Of disputed origin.
Also the origin of the surname Lado.
Indo-European
Romance
Portuguese lato, Catalan lat, Italian lato, Aromanian lat, Romanian lat
Celtic
Old Irish con·slá? "to go away," a connection posited by de Vaan (2014), but he has not convinced most authorities due to semantic problems. It is hard to explain the connection between "going away" and "side."
Balto-Slavic
Old Church Slavonic stьlati? "broaden." Classically linked to Latin latus, but now reconstructed in Proto-Indo-European without a laryngeal as *stel- "to place" (Rix, et al. 2001).