wash down

verb

1. To help to swallow (something, especially food or a pill) by drinking a liquid.

   “Now we just need a drink to wash it down.”

   “I had a nice beef sandwich washed down with a pint of bitter.”

2. To wash (something) completely from top to bottom.

   “You must wash the wall down well before painting.”

   “We'll wash it down with a garden hose and just a touch of soap.”

3. To send (something) down the drain by washing action.

   “There was some food residue in the sink, so she washed it down.”