Plural of darby; shackles, handcuffs, or chains used to restrain prisoners.
Origin uncertain; possibly from a proper name (like 'Derby' or a person named Darby), or from Hindustani sources. The term appeared in English criminal slang from the 18th-19th century, particularly in Australian English.
The word 'darbies' for handcuffs is so old that it's barely used anymore, but Australian and British prisoners kept using it well into the 20th century—slang for chains that's older than most countries!
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