The way language evolves - if you send a SMS text message on your mobile phone, using predictive text, and you choose to use the word “cool”, the word will initially be displayed as “book”. Both words require pressing 2665 on the keypad of a mobile phone.
Because many people cannot be bothered (or should that be bovvered?) to go back and correct this, they leave it as “book”.
Which leads to messages like “That YouTube video is so book”, and a new meaning for book entering the language. These are known as T9onyms.
