Nonsensical or trivial talk; foolish behavior or worthless decoration or ornament.
Origin uncertain but possibly from Italian 'fald' or related to 'fiddlesticks.' It appeared in English in the 18th century as a playful word for silliness, possibly influenced by folk etymology.
Folderol sounds funny because it IS funny—the word itself is bouncy and nonsensical, which is why people use it when they want to sound amusingly dismissive. It's been popular since 1700s newspapers called obviously fake stories 'pure folderol.'
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