the public declaration of the judgment passed on persons tried in the courts of the the Spanish Inquisition, followed by the execution by the civil authorities of the sentences imposed, especially the burning of condemned heretics at the stake.
1723, "sentence passed by the Inquisition" (pl. autos-da-fé), from Port., "judicial sentence or act of the faith," especially the public burning of a heretic, from L. actus de fide, lit. "act of faith." Although the Spanish Inquisition is better-known today, there also was one in Portugal.