(jak′ə·bin) noun
A pigeon with neck feathers ruffed so as to form a hood.

(jak′ə·bin) noun
1. A member of a French revolutionary society that inaugurated the Reign of Terror, 1793; dissolved, 1799.
2. Hence, an extreme revolutionist.
3. plural Dominican friars before the French Revolution. [<F Jacobin of St. James <Med. L Jacobinus <LL Jacobus James; with ref. to the church of St. James, in Paris, where they first met]