Sterile means completely free from living germs, bacteria, or other microorganisms that could cause infection or disease. When doctors prepare for surgery, they use sterile instruments that have been specially cleaned and heated to kill every tiny living thing on them. A sterile bandage comes in a sealed package that keeps it pure and germ-free until you need it.

Before people understood the importance of sterile conditions, many patients died from infections after surgery. Today, hospitals have entire sterile rooms where surgeons scrub their hands thoroughly and wear special clothes to keep everything as clean as possible.

Sterile can also describe something unable to produce offspring or grow new life. Sterile soil won't grow plants because it lacks the nutrients and organisms plants need. A sterile animal cannot have babies.

Sometimes people use sterile to describe a place that feels cold, empty, and unwelcoming, like a room with white walls, no decorations, and nothing personal about it. This meaning suggests something so clean and plain that it has lost all warmth and character. While you want a hospital operating room to be medically sterile, you probably don't want your bedroom to feel that way.