motive; kickstart(An impetus given to get a process or thing started or restarted. • ‘new investment will provide the kick-start needed to escape from recession''More)
shot in the arm(something that has a sudden and positive effect on something, providing encouragement and new activity // A stimulus or booster, something vitalizing or encouraging, as in Getting a new concertmaster was a real shot in the arm for the orchestra. This colloquial expression alludes to a stimulant given by injection. • Fresh investment would provide the shot in the arm that this industry so badly needs.'More)
prod; stimuli; boost(a piece of help, encouragement etc.); stimulus(something that causes a reaction in a living thing; something that rouses or encourages a person etc. to action or greater effort • Light is the stimulus that causes a flower to open; Many people think that children need the stimulus of competition to make them work better in school)
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