The second-fastest animal, the second-greatest wall, the second disease eliminated by humans, and the second human in orbit.
The cheetah, the Great Wall of China, smallpox, and Yuri Gagarin are famous bests or firsts. But what about second place?

The pronghorn is the second-fastest land animal because it outlived its primary predator.

The second human to orbit the Earth set many firsts: first to orbit more than once, first to vomit in space, first to sleep in space, first to pilot a space ship…

We eliminated rinderpest in 2011, making it the second disease, after smallpox, to be purposefully made extinct.

The second-greatest wall was built to keep out the Red Huns.