If you 'wipe the floor with' someone, you defeat them easily. Searching on Google, I can only see explanations of what this idiom means, but not how it came about. What caused people to start using this phrase in this way?
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According to A dictionary of slang, jargon and cant by Barrère and Leland (1897), it means that "one man has thrashed another so completely as to have taken him like a broom or mop, and swept or cleaned the floor with him."
(Rather cheekily, both usage examples there are from poems by Leland himself.)