The term FIRE SOUND can be broken down into two crossword solutions: ROAR (4 letters) and CRACKLE (7 letters). ROAR is a deep, loud sound that is often associated with large animals such as lions or tigers. It is also used to describe the sound of a fire when it is burning intensely. CRACKLE is a sharp, crackling sound that is often associated with a fire burning. It is usually caused by the burning of small pieces of wood or other materials.