n. pl. her·e·sies
a. An opinion or a doctrine at variance with established religious beliefs, especially dissension from or denial of Roman Catholic dogma by a professed believer or baptized church member.
b. Adherence to such dissenting opinion or doctrine.
a. A controversial or unorthodox opinion or doctrine, as in politics, philosophy, or science.
b. Adherence to such controversial or unorthodox opinion.
[Middle English heresie, from Old French, from Late Latin haeresis, from Late Greek hairesis, from Greek, a choosing, faction, from haireisthai, to choose, middle voice of hairein, to take.]
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