There's many names for it across cultures, though I think to put a name on it is worthless as it is seemingly beyond description. In English I've heard it called 'Flow' or even simply 'IT'. Here are some quotes from the book Free Play that may illuminate some of the theory:

"The literature of Zen, on which I have drawn heavily because of its deep penetration of the breakthrough experience, abounds with accounts of kensho and satori -- moments of illumination and moments of total change of heart."

"Spiritual traditions the world over are full of references to this mysterious juice: ch'i in China and ki in Japan (embodying the great Tao in each individual), kundalini and prana in India, mana in Polynesia, orendé and manitu among the Iroquois and Algonquins, axé among the Afro-Brazilian condomblé cults, baraka among the Sufis in the Middle East, élan vital on the streets of Paris. The common theme is that the person is a vessel or conduit through which a transpersonal force flows."