Tesla coil

American  

noun

Electricity.

1. an air-core transformer used to produce high voltages of high-frequency alternating currents.

---

tesla coil British  

noun

1. a step-up transformer with an air core, used for producing high voltages at high frequencies. The secondary circuit is tuned to resonate with the primary winding

---

tesla coil Scientific  

1. An electrical device that generates extremely high voltages, usually for the purpose of creating dramatic electric arcs and lightning effects or for producing x-rays. Tesla coils use step-up transformers to boost the voltage of a power supply and build up large charges in a capacitor. A spark gap periodically shorts out the capacitor, releasing its charge in huge current flows, that generate extremely high voltages (up to ten million volts) through an open-air transformer.

---

Etymology

Origin of Tesla coil

First recorded in 1900–05; named after its inventor, N. Tesla

Example Sentences

There’s a Tesla coil, and we will test out various electrical energy reactions.

From Los Angeles Times • May 8, 2025

While still in high school, Markham and a friend, Tom Sheally, built a Tesla coil that could make lightning 3 or 4 feet long.

From Washington Times • Oct. 31, 2020

In Griffith Park, we oozed uphill through heavy traffic toward the Tesla coil.

From Slate • Oct. 2, 2020

Björk’s live shows are ever-shifting experiences – you never know if you’ll get a full orchestra, a giant musical Tesla coil or a 12-strong flute club.

From The Guardian • Apr. 7, 2020

Merle Tuve, who was still struggling to produce high-energy particles with his obstreperous Tesla coil, saw little practical application for Lawrence’s curved variation on a linear accelerator.

From "Big Science" by Michael Hiltzik