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libertad f. (Noun) "liberty"
13th cent. From libertas 'id.,' from liber "free" and -tas (see libre and -tad respectively).
Indo-European
Romance
Portuguese liberdade, Galician liberdade, Catalan llibretat, French liberté, Italian libertà, Romanian libertate

"Although the opposition “free/slave” is common to all Indo-European peoples, a common designation of the notion of “liberty” is unknown." ~ E. Benveniste, Indo-European Language and Society (1973)