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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.
Portuguese lato, Catalan lat, Italian lato, Aromanian lat, Romanian lat
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."
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).