MAJOR HEADACHE is a phrase that can be used to describe a difficult problem or situation that causes a lot of stress and frustration. The term can also be used to describe a severe headache, which is a physical pain that can be caused by a variety of medical conditions. In this crossword, the solution for MAJOR HEADACHE is HASSLE, which is a synonym for a difficult problem or situation. HASSLE is a six-letter word that can be used to describe a major headache, both figuratively and literally.