The term 'Blade in the Pen' is a metaphor for the Shiv, which is a four-letter word. The phrase is used to describe someone who is a skilled writer and has the ability to craft words with precision and accuracy. It is also used to refer to someone who is a master of their craft and can use their words to create powerful and meaningful messages. The phrase is often used to describe writers who have a unique style and can use their words to make an impact on their readers.