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

See Examples For:

fourth dimension

General relativity, proven accurate by countless tests and observations, suggests that gravity impacts not simply three physical dimensions but also a fourth dimension: time.

From Science Daily ● May 1, 2024

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

From Seattle Times ● Feb. 2, 2024

Time melds a fourth dimension to the three we identify as essential to understanding space.

From Los Angeles Times ● Nov. 12, 2022

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

From Washington Post ● May 22, 2020

The fourth dimension, time, is also finite in extent, but it is like a line with two ends or boundaries, a beginning and an end.

From "A Brief History of Time: And Other Essays" by Stephen Hawking