Polpettone comes from polpetta with the addition of the augmentative suffix -one.
I have never eaten either polpettone or meatloaf, because both are famous for being particularly demanding on our digestive system, a character I dislike in food. This defining trait of polpettone explains the metaphorical use of the word to describe something muddled and boring. Movies and books are at particular risk of being condemned as polpettoni.
Click on the button to hear me pronounce the Italian words mentioned in the post:
or launch the polpettone audio file [mp3].
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