To dredge means to scoop mud, sand, or debris from the bottom of a river, harbor, or lake. Imagine using a giant underwater shovel to clean out a waterway. Ships carrying cargo need deep water to travel safely, but rivers and harbors naturally fill with sediment over time. Dredging machines remove this buildup, creating channels deep enough for large vessels to pass through.

The process uses specialized equipment called a dredge, which might work like an enormous vacuum cleaner sucking material from the bottom, or like a huge claw scooping it up. Cities with busy ports dredge their harbors regularly to keep commerce flowing. Sometimes dredging helps create new land: workers pile the removed material to build up shorelines or create islands.

The word also means to coat food lightly with flour, breadcrumbs, or another dry ingredient before cooking. When you dredge chicken in flour before frying it, you're creating a crispy outer layer.

You might hear someone say they dredged up an old memory or story, meaning they pulled something long-forgotten from the depths of their mind, similar to how dredging brings hidden things up from underwater.