throw something overboard
throw (something) overboard
To dispose or get rid of something or someone. Likened to throwing something over the side of a ship. In a major corporate shake-up, most of the company's upper-level management was thrown overboard at the end of the fiscal year. I know it's a really bad habit, but we just throw our rubbish overboard when travelling on a long car journey.
throw something overboardabandon or discard something.
The idea here is that something thrown over the side of a ship is lost forever.