[brothers ]. Applied to the four great religious orders —Dominicans, Franciscans, Augustinians, and Carmelites. Later, a fifth order was added—that of the Trinitarians. The first two were called Black and Grey friars, the Carmelites were called White friars, and the Trinitarians Crutched friars (q.v. ).
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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