sparkplug definition by American Heritage Dictionary
transitive verb spark·plugged, spark·plug·ging, spark·plugs Informal
To inspire or energize (an endeavor, for example).
Variant of spark plug
- an electrical device threaded into the cylinder of an internal-combustion engine to ignite the fuel mixture by producing timed sparks between electrodes
- Informal a person or thing that inspires, activates, or advances something