1. A radical or extreme leftist.
2. A radical republican during the French Revolution.
3. A Dominican friar.
[Middle English, Dominican friar, from French, from Old French (frere) jacobin (translation of Medieval Latin (frāter) Iacōbīnus, Jacobinic brother, from Iacōbus, James, after the church of Saint Jacques in Paris, near which the friars built their first convent). Sense 2, from the fact that the Jacobins first met in the convent.]
Jac′o·binic, Jac′o·bini·cal adj.
Jaco·bin·ize′ (-bĭ-nīz′) v.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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