from The American Heritage® Dictionary of the English Language, 4th Edition
- n. The unit of magnetic flux density in the International System of Units, equal to the magnitude of the magnetic field vector necessary to produce a force of one newton on a charge of one coulomb moving perpendicular to the direction of the magnetic field vector with a velocity of one meter per second. It is equivalent to one weber per square meter.
Comparatively, a medical MRI machine has a magnetic force of 1 tesla, meaning it is far stronger than the Milky Way's core.
The use of the transformer in the Tesla apparatus is merely to charge a condenser, and thus it is seen that an ordinary induction coil or even a static machine of the dimensions could be used, but they are not nearly as handy.
This word is named for Nikola Tesla, the inventor, engineer, and futurist.