Who are the Creoles?
Creoles are a group of people (and their descendants) born in the Louisiana colony with parents from the old world (predominantly Spain or France). During the colonial period, the Spanish and French governments considered them equal citizens, but typically refused to issue them high ranking government and church positions or titles, which they reserved for their citizens from Europe. This caused rebellions, most notably in Mexico.
In the late 1600s and into the early 1700s, the definition and use of the term Creole expanded to include those born in the colony of mixed ancestry (Spanish/French and Native American). The definition and use continued to evolve to include all of the above as well as those born in the colony of mixed ancestry (Spanish/French and Native American or African). Special care was taken not to include Acadians in the definition of Creole. Acadians are Cajuns.
Since Creole is a colonial term, your ancestor must have resided within the borders of present-day Louisiana prior to the 1803 Louisiana Purchase, which ended the colonial period.