Foucault pendulum
Noun
Meaning
pendulum with a long wire; can swing in any direction; the change in the swing plane demonstrates the earth's rotation
Source: WordNetHypernyms
Examples
Physical Review Letters vol. 107, paper 152501 MEMS A MEMS gyroscope takes the idea of the Foucault pendulum and uses a vibrating element, known as a MEMS (microelectromechanical system).
In 1851, Léon Foucault showed the Earth's rotation with a huge pendulum ( Foucault pendulum ).