A plunger is a simple tool used to clear clogged drains and toilets. It consists of a wooden or plastic handle attached to a large rubber cup. When you push the plunger down over a drain and pull it back up quickly, it creates suction and pressure that can dislodge whatever is blocking the pipe. The rhythmic pushing and pulling forces water back and forth through the clog until it breaks apart and flows away.

Many households have one tucked away somewhere, usually near the bathroom. While it's not the most glamorous tool in the house, a plunger can save the day when a toilet backs up or a sink won't drain. Using a plunger effectively takes a bit of technique: you need to create a good seal around the drain opening and then push and pull with steady force.

The word can also describe anything that plunges or pushes downward in a similar motion. Some coffee makers use a plunger mechanism to separate the grounds from the brewed coffee: you push the plunger down through the pot to trap the grounds at the bottom. The key idea is something that pushes or forces its way through.