A low, vulgar fellow; an omnibus conductor. Either from cadet, or a contraction of cadger (a packman). The etymology of cad, a cadendo, is only a pun. N.B.- The Scotch cadie or cawdic (a little servant, or errand-boy, or carrier of a sedan-chair), without the diminutive, offers a plausible suggestion.
“All Edinburgh men and boys know that when sedan-chairs were discontinued, the old cadies sank into ruinous poverty, and became synonymous with roughs. The word was brought to London by James Hannay, who frequently used it.” —M. Pringle.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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