'A whopper' is often used to mean a big (and obvious) lie. 'He told me a whopper' means that he lied shamelessly about something.

The Whoppers at Hungry Jacks/Burger King are fantastic: flame grilled beef patty, a bun made of real bread, lots of onion and lettuce and a tomato sauce, cucumbers. A meal in itself. A 'whopper' is something big - a big lie, a big mistake, a huge problem. A whopper of a mistake/stuff up. He did a whopper in the pool - maybe a big dive/splash, etc. Anything really big is a whopper.

Hi Michael! Fishermen are all the same throughout the world, they exaggerate their catches :)

That's a special usage by your friend I think ! Mostly, a whopper is a great big thing - anything, but sometimes a fish - and then very often it's a great big lie. Fishermen, in popular myth, have a reputation for lying about the size of the fish that they caught. They'll tell you it was a great big one, a whopper. So the lie usage was born ... it's probably not a true story, but I like it. ;)

Need to try it:) Thank you Carol!