Ventral describes the belly side or underside of an animal's body. A fish's ventral fins are on its underside, helping it steer and balance as it swims. A frog's ventral surface is its pale belly, while its back is darker to help it blend in with pond water.

Scientists and biologists use ventral as the opposite of dorsal, which means the back side. When you look at a butterfly with its wings spread out, you're seeing its dorsal side. Flip it over carefully, and you're looking at its ventral side.

You might see it in nature documentaries: “The shark's ventral side is white, making it harder for prey to spot from below.” In anatomy books, diagrams often show both the dorsal view and the ventral view of animals so you can see all their features.

For humans, doctors sometimes use ventral to describe the front of the body, though they more commonly say “anterior” instead. But when studying fish, reptiles, insects, or other animals, ventral is the standard scientific term for describing that belly-side region.