to·​roid | \ ˈtȯr-ˌȯid How to pronounce toroid (audio) \

Definition of toroid

1 : a surface generated by a closed plane curve rotated about a line that lies in the same plane as the curve but does not intersect it
2 : a body whose surface has the form of a toroid

Examples of toroid in a Sentence

Recent Examples on the Web So, although the vacuum vessel is still basically a toroid, the magnets that loop around the tube are not planar. Chris Lee, Ars Technica, "Wibbly-wobbly magnetic fusion stuff: The return of the stellarator," 9 June 2017

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

First Known Use of toroid

1886, in the meaning defined at sense 1

History and Etymology for toroid

New Latin torus

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The first known use of toroid was in 1886

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Cite this Entry

“Toroid.” Dictionary, Merriam-Webster, Accessed 3 Jul. 2020.

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