Cockney rhyming slang, a dialect which dates back 175 years, could be in danger of dying out.
New research reveals how 18-24-year-olds are failing to recognize once famous phrases such as Cream Crackered, Donkey's Ears and Rosie Lee.
According to the survey, a fifth of people under-25 thought 'Bottle and Stopper' was a reference to Burger King's Whopper. In case you're wondering it's actually Copper.
Cockney rhyming slang originated in the 1840s. To classify as a cockney, a Londoner had to be born within the sound of Bow Bells at St Mary-le-Bow.
Researchers say changes in society are making phrases increasingly redundant, with new generations making up their their own sayings.
Test your own knowledge of cockney rhyming slang with our quiz below. Answer all 15 questions to get your results.