Poppycock is nonsense or foolish talk that doesn't make any sense. When someone tells you that eating carrots will let you see in complete darkness, or that the moon is made of green cheese, you might respond, “That's poppycock!” The word has a playful, old-fashioned sound to it, like something your great-grandmother might have said when she heard something ridiculous.

You'll often hear poppycock used to dismiss claims that sound impressive but fall apart under examination. If someone insists they can run faster than a car or that they invented homework, a skeptical listener might call it poppycock. The word suggests that something is obviously, almost comically wrong, so absurd that it doesn't deserve serious consideration.

Poppycock is stronger than simply saying “I disagree.” It means the idea is so absurd it doesn't deserve serious consideration. When a character in a story declares something to be poppycock, they're usually a no-nonsense person who values truth and has little patience for exaggeration or tall tales.