The Collaborative International Dictionary of English v.0.48:
auto-da-fe \auto-da-fe\, Auto-da-f'e \Au"to-da-f['e]"\, n.; pl.
Autos-da-f['e]. [Pg., act of the faith; auto act, fr. L.
actus + da of the + f['e] faith, fr. L. fides.]
1. A judgment of the Inquisition in Spain and Portugal
condemning or acquitting persons accused of religious
2. An execution of such sentence, by the civil power, esp.
the burning of a heretic. It was usually held on Sunday,
and was made a great public solemnity by impressive forms
3. Hence: [Fig.] The public denunciation or punishment of a
person who has offended the prevailing authorities.
4. A session of the court of Inquisition.