The two crossword solutions for the term MARVELOUS, IN SLANG are FAB (3 letters) and DREAMY (6 letters). FAB is an acronym for 'Fantastic And Brilliant' and is used to describe something that is very impressive or wonderful. DREAMY is a slang term used to describe something that is wonderful, delightful, or extraordinary. Both terms are used to express admiration for something that is considered to be marvelous.