Mameluco the word is believed to be of Arabic origin. The word in Arabic is Mamluk (masculine) or Mamluka (feminine) مملوك (masculine) or مملوكة (feminine). The word Mameluco is a term of Portuguese origin describing the first generation offspring of a European and an Amerindian. The corresponding Spanish word is mestizo.
In the 17th and 18th centuries, Mameluco was used to refer to organized bands of slave-hunters, also known as bandeirantes, who roamed the interior of South America from the Atlantic to the foothills of the Andes, and from Paraguay to the Orinoco river, invading Guarani-occupied areas in search of slaves.
The word may have become common in Portugal in the Middle Ages, deriving from the Arabic 'mamlûk', used in the association with the Mamluks.