The term 'all business' can be summarized by two crossword solutions: 'STERN' and 'NONSENSE'. 'STERN' is a 5-letter word meaning serious, strict, or harsh. It is often used to describe someone's demeanor or attitude. 'NONSENSE' is a 10-letter word meaning something that is absurd, foolish, or illogical. It is often used to describe something that is not true or does not make sense. Together, these two words can be used to describe someone who is serious and focused on their work, with no time for foolishness.