REALLY (7 letters) The term 'Truly Mad' can be broken down into two crossword solutions: INSANE (6 letters) and REALLY (7 letters). INSANE is an adjective used to describe someone who is mentally ill or unstable, while REALLY is an adverb used to emphasize the truth of a statement. Together, these two words form the phrase 'Truly Mad', which is used to describe someone who is not only mentally unstable, but also deeply passionate about something.