👉 The term "capillary" refers to a type of liquid or gas that exists in a vacuum and is able to flow through small openings. This process can be used for various purposes, such as collecting liquids from containers, measuring pressure changes, or extracting gases from a container. The word comes from the Greek words "capilla," which means "mouth" or "waterway," and "cilia," which are tiny hairs on the surface of liquid surfaces that help to collect water droplets.