The sounds of stomachs growling are caused by contractions and movement of air and gas; mixed with fluids in the digestive system to make a rumbling, gurgling, or growling sound. This can occur inside the stomach, and also the intestines. The noises can happen regularly, but are heard louder when the stomach and intestines are empty after several hours without eating, which causes the air and gas pockets to make a more audible growling sound. Stomach growling is translated borborygymi, and indicates hunger, digestion, or gas moving around inside the belly.
Usually represented in Japanese with the sound "guu" (ぐう).
