transitive. To cause or force (a horse or other animal) to run (sense 1a), esp. when riding it; (in later use also) to force (a person) to move…

Without implication of sudden onset of movement. transitive. To ride (a horse) at full speed. Obsolete. rare.

causal. To cause to run, exercise in running; to give (a horse) a run; to use (greyhounds) in coursing.

transitive. To make (a horse) career.