(A ). A black preaching gown; once used in some Anglican churches, and still used by some Dissenters in the pulpit. So called from Geneva, where Calvin preached in such a robe.
“The Nonconformist divine leaves his vestry in his black Genevan, toadied by his deacons and elders.” —Newspaper paragraph, July 18th, 1885 (on Sunday bands).
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894