a very small piece of fire that flies out from something that is burning, or one that is made by rubbing two hard things together, or a flash of light made by electricity
As he welded the two pieces of metal together, sparks flew everywhere.
As they rubbed the sticks together, a spark ignited, starting the campfire.
The professor's lecture on quantum physics sparked my interest in the subject.
A small spark from the faulty wiring caused the fire in the old building.
The entrepreneur's innovative idea was the spark that led to the creation of a successful startup.
