The crossword solution for the term LIKE A DUMBBELL is 'DENSE', which is a five-letter word. DENSE is an adjective that is used to describe something that is closely packed together or having a high concentration of something. It can also be used to describe someone who is slow to understand or learn something. In this case, it is being used to describe something that is like a dumbbell, which is a piece of exercise equipment consisting of two weighted discs connected by a short bar.