When one has an idea that sounds like it could be a part of a ficton's canon.
Will generally leave behind a trail of confused people until properly explained.
"I've had an idea! It all fits in with the canon! The generic macguffin could have been used way before by the bad guy!"
"That's called a canon spark. I'm calling that a canon spark."
"...When has that ever been called a canon spark?"
by R. Sposchki August 24, 2018
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