1. to clean up someone or something by washing.

1. Please wash the baby up as long as you are changing the diaper.

2. I’ll wash up the baby.

3. Sam will wash himself up before dinner.

2. [for water or the waves] to bring someone or something up onto the shore or beach

1. Look what the waves washed up! A bottle with a note in it!

2. The waves washed a bottle up.

3. Spilled oil has washed up on beaches behind the wreck.