Bombast refers to speaking or writing that's pompous, showing off with fancy words without sincerity. The politician's speech was pure bombast, filled with grand words that meant little.
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Negative Connotation
Using bombast carries a negative implication that the speaker is trying to deceive or impress falsely. The author's bombast failed to hide the weaknesses in his argument.
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Overly Dramatic
Bombast can be seen as overly dramatic or theatrical in a way that can seem ridiculous. The actor's bombast made the character seem less believable, rather than more powerful.