wash down(verb)

eat food accompanied by lots of liquid; also use metaphorically

"She washed down her dinner with a bottle of red wine"; "He washes down his worries with a nightly glass of whisky"

wash down, flush down(verb)

flow freely

"The body washed down the river"

wash down(Verb)

To help to swallow by drinking a liquid, after eating something, or taking a pill.

wash down(Verb)

To wash something completely from top to bottom.