impetus Synonyms

incentive encouragement propulsion driving force incitement motivation catalyst stimulus impulse impulsion spur drive drift springboard stimulator stimuli go ahead reason push pulsion stimulation reviver root seed stimulant signal steam starter source stateful synergist pulsing reactant shot in the arm Spurs triggering motive force incentives impelling force propellant motivator thrust trigger urge velocity nerve impulse kick start pick-me-up motive power provocation