Plural of bounder; people who act without manners or honesty, or things that bounce or jump.
From the verb 'bound' (to jump) with the agent suffix '-er' forming 'bounder,' which evolved in British English to mean an unscrupulous person. The sense shifted from 'one who bounds' to 'one who oversteps social boundaries.'
Victorian slang dubbed dishonest men 'bounders' because they metaphorically 'jumped' over society's rules and boundaries—a clever insult that stuck around for over a century in British English.
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