A scrubber is a device that cleans something by removing unwanted materials.

In factories and power plants, scrubbers are machines that clean pollution from smoke before it goes into the air. These industrial scrubbers spray water or chemicals through the smoke to capture harmful particles and gases, the same way you might rinse dirt off your hands. Without scrubbers, factory smokestacks would release much more pollution into the atmosphere.

On ships, scrubbers clean the exhaust from engines to meet environmental regulations. Kitchen scrubbers, which you've probably seen at home, are rough pads or brushes used for cleaning dirty pots and pans.

In medicine, a scrubber can mean a machine that removes carbon dioxide from the air in submarines or spacecraft, keeping the air safe to breathe. The Apollo 13 astronauts famously had to build an emergency scrubber using duct tape and spare parts to survive their journey home.

The word can also refer informally to someone who scrubs, like a person cleaning floors, though this usage is less common today.