plug‧hole /ˈplʌɡhəʊl $ -hoʊl/ noun [countable] British English

1. the hole in a bath or sink that the water flows out of, and which you can put a plug into Synonym : drain American English

2. go down the plughole informal
a) if work or effort goes down the plughole, it is completely wasted:
Two years of hard work went right down the plughole.
b) if a business goes down the plughole, it fails and has to close

[TahlilGaran] Dictionary of Contemporary English ▲