1. (n.) Something that provokes; a stimulus\.

2. (n.) That which incites the mind, or moves to action; motive; incentive; impulse.

aggravation agitating agitation animation arousal arousing awakening bait bribe carrot clout compulsion drive driving force electrification encouragement enticement exacerbation exasperation excitation excitement exciting exhilaration exhortation exhorting fillip firing fomentation fomenting galvanization goading impellent impelling force impetus impulse impulsion incentive incitation inducement inflaming inflammation influence influencing infuriation inspiration instigating instigation interest invitation irresistible force irritation lathering up lure moment momentum motivation motive power mover needling payment pep rally pep talk percentage persuasion persuasive perturbation power pricking prodding profit prompting propulsion provocation provoking rabble-rousing rallying reward spurring steaming up stimulation stimulative stimulus stirring stirring up stirring-up sweetener sweetening temptation thrust urging wakening whet whipping whipping up working up