blowback

(blōˈbăkˌ)

1. The backpressure in an internal-combustion engine or a boiler.
2. Powder residue that is released upon automatic ejection of a spent cartridge or shell from a firearm.
3. The effect caused by recirculation into the source country of disinformation previously planted abroad by that country's intelligence service in an effort to mislead the government of another country.