Foolish or nonsensical talk; something someone says that you don't believe or that annoys you.
Origin uncertain, possibly from dialectal English or related to 'gaff' (a blunder). Appeared in American English in the late 1800s. May be onomatopoetic, imitating empty speech.
Guff is a great example of slang words that emerged in American English without clear origins—it entered the language the same time as 'baloney' and 'hooey,' all dismissive terms for lies or nonsense, showing how cultures develop coded language to call out dishonesty.
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