What is "american pika"

Chief hare \Chief" hare`\ (Zo["o]l.) A small rodent ( Lagamys princeps) inhabiting the summits of the Rocky Mountains; -- also called crying hare, calling hare, cony, American pika, and little chief hare.

Note: It is not a true hare or rabbit, but belongs to the curious family Lagomyid[ae].

The American pika (Ochotona princeps), a diurnal species of pika, is found in the mountains of western North America, usually in boulder fields at or above the tree line. They are herbivorous, smaller relatives of rabbits and hares.