Mestizo or mestiza is a term historically used in Spain, Spanish America and the Philippines that originally referred to a person of combined European and Indigenous American descent, regardless of where the person was born.

The term was used as an ethnic/racial category for mixed-race castas that evolved during the Spanish Empire. Although broadly speaking, Mestizo means someone of mixed European/indigenous heritage, and usually for someone considered a plebeian, the term did not have a fixed meaning in the colonial period. It was a formal label for individuals in official documentation, such as censuses, parish registers, Inquisition trials, and other matters.

Individuals were labeled by priests and royal officials as mestizos, but the term was also used for self identification.

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