"Propulsory" Natural Recordings by Native Speakers
Forced; compulsory.
Example: "Propulsory voting means that every citizen is required to vote, either in person or by mail."
Propugnation is not a word in the English language. It's possible that it's a misspelling or a non-standard term.
The act or device that provides the force that propels an object, especially a vehicle, forward or upward.