The term 'MOUTHS OFF TO' can be solved by two crossword solutions: 'SASSES' (6 letters) and 'SNAPSAT' (7 letters). 'Sasses' is a slang term meaning to talk back or answer back in an insolent or impudent manner. 'Snapsat' is a verb meaning to criticize sharply or reprimand someone. Both terms refer to speaking out in a disrespectful way, usually in response to someone else's words or actions.