Cursorial is a biological term that describes an organism as being adapted specifically to run. It is typically used in conjunction with an animal's feeding habits or another important adaptation. For example, a horse can be considered a "cursorial grazer", while a wolf may be considered a "cursorial predator".
In evolutionary theory
The cursorial (or Ground-Up) theory of the evolution of flight is the theory that birds evolved from ground-living theropods, as opposed to arboreal species. This refers to the presumed cursorial nature of theropod dinosaurs, and that the flight apparatus may have been adapted to improve hunting by lengthening leaps and improving maneuverability.