: the tibia of a bird.

What is a tibiotarsus?

tibiotarsus. / (ˌtɪbɪəʊˈtɑːsəs) / noun. the bone in the leg of a bird formed by fusion of the tibia and some of the tarsal bones.

Why is the tibia bone of a bird called the tibiotarsus?

In mammals that bone is known as the tibia, so why is it called the "tibiotarsus" in birds? Well, it's more than just a tibia. It's actually a tibia with tarsal (ankle) bones fused into the distal end of the bone.