Definition of "backwash"

(nautical) The backward flow of water from oars or propeller or breaking waves.  quotations  examples

The similar flow of air from an aircraft engine.  examples

The result or consequence of an event; an aftermath.  examples

The saliva, spit or food particles that have flowed back into a drink after someone has drunk from it.  examples

(economics) The situation where economic growth in one area harms other areas by attracting people and business away from those areas.  examples

To operate a water filter in the reverse direction in order to clean it.  examples

(transitive) To affect with backwash.  examples

To clean the oil from wool after combing.  examples