Do you speak fluent teenage? The chances are almost certainly not, even if you're a teenager yourself
Test yourself with our quiz
Researchers for a new Penguin dictionary have uncovered huge differences in what's cool and what's not among teenagers across the UK.
Cool is still the most popular word in the UK, followed by wicked, groovy, bling-bling, mint and kerching.
But, there are some words which simply don't travel, according to researchers.
We talked to Maggie Philbin - and to the editor of Mizz Magazine, Sharon Christal
Try our interactive quiz to see how you measure up - and send us your own suggestions for new words using the e-mail form on the right hand side
The Penguin English Dictionary is published on August 7. It costs £18.99