noun Physics, Electricity.
- a device for producing high-voltage static electricity.
- a device for producing high electrostatic potentials (up to 15 million volts), consisting of a hollow metal sphere on which a charge is accumulated from a continuous moving belt of insulating material: used in particle accelerators
- A type of electrostatic generator used to build up static electrical charge of very high voltages by transferring electric charge from a power supply to a spherical metal terminal. A high-voltage source transfers charge to a nonconducting conveyor belt, usually made of silk or rubber, which continuously redeposits the charge on the insulated metal terminal, where it accumulates. Even small Van de Graaff generators can accumulate a static charge of 100,000 volts; the largest, up to 10 million volts.