Dhananjaya Vayu is one of the vital in human body. It nourishes the whole body, maintains the well-being of all the organs and retains their freshness and appearance for some time even after death.
It is said that dhananjaya vayu is found everywhere in the body and its parts after death. A similar description is found in Yoga Yajnavalkya (IV. 48-72).
As per Hinduism, in the human body there are ten vayus or pranas (vital airs), which flow along channels called nadis and provide the life force required to carry on various functions. There are five chief vital airs called paranas and five subordinate or less important ones called upa prana or upa vayus.
The concept of vayu as a source of life activity and energy is as old as Vedas. The names of five main vayu are mentioned in Yajur Veda (VII.27) and in Brihadaranyaka Upanishad (I.5.3) and Chandogya Upanishad (I.3.3).
All the ten vayus are mentioned in the Trisikhi Brahmana Upanishad along with their locations in the body and their functions (77-87).
The ten pranas are prana, apana, samana, udana, vyana, naga, kurma, krkara, devatta and dhananjaya.
The ten vayus are also mentioned in the Mahabharata (Vana Parva 21.3-16). They are called dasa pranah, meaning the ten pranas.
In terms of modern physiology, the vayus are explained by some scholars as nervous impulses. However, it has not been possible yet to explain ten different forms of the impulses in relation to different functions.