blowdown

(countable, uncountable) The removal of liquid and solid hydrocarbons from a refinery vessel by the use of pressure.
(countable, uncountable) Cooling fluid discharged from a plant at the end of its cycle.
(countable, uncountable) Uprooting, overtopping, or bole breakage of trees by the wind; windthrow and windsnap.
(countable, uncountable) The action of aerodynamic forces to tend to cause a deflected control surface to return to its neutral position, or prevent the surface from deflecting past a certain point.
(countable, informal, uncountable) An instance of blowing down with compressed air.