›to take money, especially dishonestly, and use it for a purpose for which it was not intended: siphon off funds/millions/moneysiphon sth from sthHe siphoned €600,000 from company accounts to pay for his secret lifestyle.siphon sth awayMillions of dollars of city funds were siphoned away in the form of fake property tax refunds.
›NATURAL RESOURCESto remove a liquid from one place and put it in another using a pipe or tube: The government decided to scrap its plan to siphon water from the North-East of the country to the parched South.