permeate

When you live in a big city like New York, you know all too well how the smells of spices and cooking meats can permeate a hallway, easily passing through those thin apartment doors to make your mouth water.

The verb permeate literally means to "pass through." It's often used to describe smells or liquids that not only pass through, but also spread to fill an entire area. When you bake cookies, you'll notice that the rich, sweet smell of those cookies isn't confined just to your oven — it permeates the entire kitchen and even the whole house. In science class, you might have learned about a permeable membrane — a thin material that is porous enough to let liquids or gases to pass through.