Aeration means adding air to something, usually water or soil.

When you see a fish tank with bubbles rising from the bottom, that's aeration at work. The bubbles mix oxygen into the water so the fish can breathe. Without aeration, the water would become stale and the fish could suffocate. Aquariums use pumps to keep water constantly aerated.

Gardeners care about soil aeration too. When soil gets packed down hard, plant roots can't get the oxygen they need to grow. That's why gardeners turn and loosen their soil: they're aerating it, creating tiny air pockets that let roots breathe and water drain properly. Earthworms are natural aerators, constantly tunneling through soil and creating channels for air to flow.

You'll also hear about aeration in water treatment plants, where workers aerate drinking water to remove unpleasant tastes and odors, or on golf courses, where groundskeepers aerate the grass by poking holes in the turf so air and water can reach the roots. The process of aeration happens whenever air gets mixed into something that needs it, whether that's your fish tank, your garden, or even a glass of wine that needs to “breathe” before drinking.