to·​ka·​mak | \ ˈtō-kə-ˌmak How to pronounce tokamak (audio) , ˈtä- How to pronounce tokamak (audio) \
variants: or less commonly tokomak

Definition of tokamak

: a toroidal device for producing controlled nuclear fusion that involves the confining and heating of a gaseous plasma by means of an electric current and magnetic field

Examples of tokamak in a Sentence

Recent Examples on the Web So in a tokamak reactor, plasma is heated more and more until its charged ions start to merge. Caroline Delbert, Popular Mechanics, 18 Feb. 2022 This pumps out the diverted particles and removes any excess heat to protect the tokamak. David Donovan, The Conversation, 4 Apr. 2022 So what goes wrong with magnets in a typical tokamak run? Caroline Delbert, Popular Mechanics, 18 Feb. 2022 The inner vessel wall of the tokamak was upgraded from graphite to beryllium. David Donovan, The Conversation, 4 Apr. 2022 Tokamak Energy, an amusingly hard-to-Google company based in Oxford in the south of England, has been working on tokamak reactors since 2009. Caroline Delbert, Popular Mechanics, 1 Apr. 2022 The tokamak comes courtesy of the Swiss Plasma Center at the EPFL in Lausanne. John Timmer, Ars Technica, 16 Feb. 2022 Developing the control software for a tokamak is a complicated process. John Timmer, Ars Technica, 16 Feb. 2022 For about ten years, the original JET tokamak operated with the same goal that fusion projects have today: to generate enough energy to be productive against the fusion reactor's enormous energy cost for operation. Caroline Delbert, Popular Mechanics, 16 Feb. 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'tokamak.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of tokamak

1965, in the meaning defined above

History and Etymology for tokamak

Russian, from toroidal'naya kamera s aksial'nym magnitnym polem (toroidal chamber with an axial magnetic field)

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The first known use of tokamak was in 1965

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Cite this Entry

“Tokamak.” Dictionary, Merriam-Webster, Accessed 8 Aug. 2022.

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