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saca (2) m. (Noun) "large sack"
Very late 15th cent. From saco.
Corominas, J. & J. Pascual. Diccionario crítico etimológico castellano e híspanico. 6 vols. Madrid: Gredos. 1991-1997.
Real Academia Española. Diccionario de la lengua española. Online. 23rd ed. Madrid: Espasa Calpa. 2014. http://www.rae.es/.