The term 'GUNKY STUFF' can be defined by the following crossword solutions: GOOP (4 letters), SLIME (5 letters), GOO (3 letters), CRUD (4 letters), and GLOP (4 letters). All of these words refer to a thick, slimy, and often sticky substance. GOOP is a term used to describe a thick, viscous liquid, while SLIME is a more general term for a wet, slimy substance. GOO is a slightly less viscous version of GOOP, while CRUD is a more general term for a dirty, messy substance. Finally, GLOP is a term used to describe a thick, slimy, and often sticky substance.