The term 'Root of All Evil' is often used to refer to MONEY, which is the five-letter solution to this crossword. This phrase is derived from a biblical passage in 1 Timothy 6:10, which states that 'the love of MONEY is the root of all kinds of evil'. This phrase has been used to describe the idea that MONEY can be a corrupting influence, leading people to do immoral or unethical things in order to gain more wealth.