what's the idea

Idioms  

1. Also, what's the big idea; the very idea. What do you think you are doing? What foolishness do you have in mind? For example, What's the idea of taking the car without permission? or You've invited yourself along? What's the big idea? or Take a two-year-old up Mount Washington? The very idea! These phrases, all implying the speaker's disapproval, use idea in the sense of “what one has in mind.” The first two date from about 1900; the third is heard more in Britain than America.

---

Example Sentences

“What’s the idea, am I being watched? Stuck somewhere where it’ll be easier to tell if anyone comes to see me?”

From Literature

What’s the idea behind your argument?

From New York Times

In a tweet on Thursday morning, the pub chain asked the retailer "what's the idea with these T-shirts!?"

From BBC

“My Gramsy always says it’s raining cats and dogs, but what does that even mean, anyway? … It makes just as much sense to say it’s raining giraffes and naked mole rats. … Why not say it’s raining crayons and spatulas? And what’s the idea with umbrellas anyway?”

From Los Angeles Times

Nobody had done it before, so what’s the idea?

From Los Angeles Times