wash down

verb3

1. •
   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.
2. •
   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.
3. •
   To send (something) down the drain by washing action.

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