Relating to or characterized by beliefs or opinions that differ from established or conventional ones.
From Greek heterodoxos (different opinion), combining hetero- (different) + doxa (opinion or belief). The '-al' ending makes it an adjective form of heterodoxy.
Galileo's heterodoxal idea that Earth orbits the Sun instead of the reverse got him in serious trouble with the church—it took 300 years for science to fully vindicate him!
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