Longman Dictionary of Contemporary English
Wiktionary
a. Of or relating to washing dishes. n. (context British English) The act of washing dishes etc; dishwashing.
WordNet
n. the washing of dishes etc after a meal
Usage examples of "washing-up".
I went below to do the washing-up, tossing the slops out of the porthole into the sea.
After dinner we decided that Sunday afternoon was a bad time to go round the village asking for charity, because money given away on Sunday was for church collection, and anyway, all the grown-ups would be taking their Sunday afternoon siesta and would not be pleased at having to get up and answer the door, so, to repay Aunt Lally for her kind contribution to our missionary box, we went to her while she was doing the washing-up and asked for something Sundayish to read.
The bowl of washing-up water he takes outside to empty over the alpines: no water should be wasted at a time of shortage.
He prepared a sicklier version -- whiskey and port-style British wine diluted with warm water from the washing-up tap -- and this too was well appreciated.
Wendy points out that most of these jobs already have waiting lists, even washing-up, as there are far more prisoners than jobs.