The act of cheating or defrauding; engaging in dishonest financial dealings with someone.
From 'gyp' (to cheat) + '-ing' (present participle suffix), using the same problematic root. An archaic slang term formed according to standard English verb rules.
What's interesting linguistically is that even though this word and its variations are now considered offensive and obsolete, they show exactly how productive English is at creating new words from existing roots—it's a reminder of language's power to spread (or challenge) prejudices.
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