In the context of understanding how the body works, pavan, also called vayu, refers to the oxygen and carbon dioxide contained in it. It is also related to wisdom and the mind, as well as to the spirit.
The word is used to signify any part of the overall network of breath and wind in the world, including the first winds that blew when the universe was created. The five elements are also associated with the five senses, with pavan being associated with the sense of touch.
The importance of pavan is seen in the fact that pranayama (control of the breath) plays such a vital part in yoga practice.