Thing is, there are plenty of books that are called “comics” for various reasons, such as Maus, compilations of weekly publications of a non-strip serial (e.g. tankobons)*, and some other cases.
*compare to how many classic novels, e.g. work by Charles Dickens, were initially published chapter-by-chapter but are now read as compilations. Many manga as well as western comics also get published this way (e.g. I have an old Daredevil book that was originally published on a monthly basis but reads just fine consecutively as a unified book)
IMO “graphic novel” is a little more specific. Long-running superhero or manga series aren’t graphic novels, nor are newspaper comics.
Thing is, there are plenty of books that are called “comics” for various reasons, such as Maus, compilations of weekly publications of a non-strip serial (e.g. tankobons)*, and some other cases.
*compare to how many classic novels, e.g. work by Charles Dickens, were initially published chapter-by-chapter but are now read as compilations. Many manga as well as western comics also get published this way (e.g. I have an old Daredevil book that was originally published on a monthly basis but reads just fine consecutively as a unified book)