fourth dimension

American  

noun

1. Physics, Mathematics. a dimension in addition to length, width, and depth, used so as to be able to employ geometrical language in discussing phenomena that depend on four variables.

   Time is considered a fourth dimension for locating points in space-time.

2. something beyond the kind of normal human experience that can be explained scientifically.

   The story deals with ESP and other excursions into the fourth dimension.

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fourth dimension British  

noun

1. the dimension of time, which is necessary in addition to three spatial dimensions to specify fully the position and behaviour of a point or particle

2. the concept in science fiction of a dimension in addition to three spatial dimensions, used to explain supernatural phenomena, events, etc

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fourth dimension Scientific  

/ fôrth /

1. Time regarded as a coordinate dimension. A fourth dimension is required by relativity theory, along with three spatial dimensions, to specify completely the location of any event.

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Other Word Forms

• fourth-dimensional adjective

Etymology

Origin of fourth dimension

First recorded in 1870–75

Example Sentences

And, because of the magic of light, the fourth dimension of time is constantly added.

From Seattle Times • Feb. 2, 2024

Spacetime is just a mathematical object consisting of the three dimensions of space, and time considered as a fourth dimension.

From Science Daily • Dec. 4, 2023

The fourth dimension offers unlimited space in which to unravel even the most complicated knot.

From Washington Post • May 22, 2020

Toward the end of the afternoon, he is asked about that moment in the Farewell shows where he steps through the door in the video screen and into the fourth dimension of his own history.

From Los Angeles Times • Oct. 14, 2019

He could hear it in his head, and like a crack in the fourth dimension, a fracture of the Euclidean plane, Sergio could watch it happening on the television.

From "Nine, Ten: A September 11 Story" by Nora Raleigh Baskin