a) The form that energy can take when either ascending or descending vertically. Usually found in groups of up to seven terminating in a toroid, joined either point to point or base to base. In some cases, at these junctions the flow of the energy can change from clockwise to anticlockwise or vice-versa. Change in polarity from negative to positive can also occur. Vortices are a common feature where energy lines intersect. Rising vortices are commonly found over blind springs, descending vortices are found where two water veins cross.
b) Also used (mainly in North America) to refer to areas where various magnetic and gravitational anomalies may be detected, often accompanied by time and space distortions. The area of influence of such vortices is said to be 54 miles in diameter and connects into larger earth grid patterns.
(Source: British Dowsing, britishdowsing.net)