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lamentar (Verb) "to be sorry," "to lament"
15th cent. From lamentare 'id.,' from lamentum "lament" (see lamento).
Indo-European
Romance
Portuguese lamentar
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/.