fourth dimension


Definition of fourth dimension

1 : a dimension in addition to length, breadth, and depth specifically : a coordinate in addition to three rectangular coordinates especially when interpreted as the time coordinate in a space-time continuum
2 : something outside the range of ordinary experience

Other Words from fourth dimension

fourth-dimensional adjective

Examples of fourth dimension in a Sentence

Recent Examples on the Web Perhaps as a consequence, in the late 19th and early 20th centuries, the public became infatuated with the fourth dimension. Quanta Magazine, 13 Sep. 2021 Physicists have struggled to understand how the time of quantum mechanics can be reconciled with the notion of time as the fourth dimension in Einstein’s general theory of relativity, the current description of gravity. Quanta Magazine, 31 Aug. 2021 What would a fourth dimension — somehow perpendicular to our three — look like? Quanta Magazine, 13 Sep. 2021 By 2014, plenty of people had worked on the game theory of cooperation, the authors wrote, but that canon tends to ignore the fourth dimension—time. Adam Rogers, Wired, 1 July 2021 Not a physical entity, the fourth dimension could be felt as a type of transcendence, transmitted by the artist to a particular viewer through art. William C. Agee, WSJ, 25 Dec. 2020 Einstein unified the three dimensions of space with the fourth dimension of time, and this spacetime will warp and stretch in the presence of a mass or equivalent distortion. Jennifer Ouellette, Ars Technica, 20 Nov. 2020 Matthew Salesses considers the impact of his wife’s passing, and other factors, on his experience as a human passing through the fourth dimension. Sari Botton, Longreads, 13 May 2020 Though it was published a full decade before Einstein's theory of relativity, the book treats time as a fourth dimension, independent of the three dimensions of space, similar to how it is conceived in Einstein’s physics. Quanta Magazine, 5 May 2020

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

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First Known Use of fourth dimension

1875, in the meaning defined at sense 1

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Time Traveler for fourth dimension

Time Traveler

The first known use of fourth dimension was in 1875

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Dictionary Entries Near fourth dimension

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fourth dimension

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Statistics for fourth dimension

Last Updated

23 Oct 2021

Cite this Entry

“Fourth dimension.” Dictionary, Merriam-Webster, Accessed 4 Dec. 2021.

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