backwash

back +‎ wash

• (UK) IPA^(key): /ˈbæk.wɒʃ/
• (US) IPA^(key): /ˈbæk.wɑʃ/

backwash (countable and uncountable, plural backwashes)

1. (nautical) The backward flow of water from oars or propeller or breaking waves.
2. The similar flow of air from an aircraft engine.
3. The result or consequence of an event; an aftermath.
4. The saliva, spit or food particles that have flowed back into a drink after someone has drunk from it.

backwash (third-person singular simple present backwashes, present participle backwashing, simple past and past participle backwashed)

1. To operate a water filter in the reverse direction in order to clean it.
2. (transitive) To affect with backwash.
3. To clean the oil from wool after combing.

• wake

• washback