Quadruped a. : Having four feet.

Quadruped n. : An animal having four feet, as most mammals and reptiles; -- often restricted to the mammals.

Example:
a Quadruped walks on all fours what walks what walks on all twos?

Taxonomy
quadrupeds, quadrupedal, Quadrupedalism, tetrapods, movement, free encyclopedia, exercise, gait, scientists, Flying and gliding animals, limbs, legs, wings, walking, crawl, Mundlos, ordination, cross.

Defination from the web:
quadruped. Quadrupedalism is a form of land animal locomotion ... The majority of walking animals are quadrupeds, including mammals such as cattle and cats, and reptiles, like lizards. ... For example, among the insects, the praying mantis is a quadruped. ...