spurrer
/ˈspɜrər/Definitions
1. noun
A person who spurs or incites others to action, often by criticism or ridicule.
“The satirist served as a spurrer for social change by highlighting the hypocrisy of the elite.”
2. noun
A device that spurs or stimulates something, especially a piece of equipment in a railway or similar system.
“The mechanical spurrer kept the train moving even in the face of heavy snow.”