back·wash 
(băkwŏsh′, -wôsh′)
(băkwŏsh′, -wôsh′)n.
1.
a. A backward flow of water, as from the action of oars.
b. See backrush.
2. A backward flow of air, as from the propeller of an aircraft.
3. A result of an event; an aftermath.
4. Informal A backward flow of liquid from the mouth into a bottle or other drinking vessel at the end of a swig.