The term 'gloppy stuff' can be broken down into two crossword solutions: GOOP (4 letters) and GOO (3 letters). GOOP is a type of thick, slimy substance that is often used in craft projects. It is made from a mixture of cornstarch and water, and can be used to make sculptures, decorations, and other art projects. GOO is a slang term for a sticky, viscous substance, such as glue or syrup. It is often used to describe a situation that is difficult to get out of, or a person who is hard to deal with.