fourth dimension

noun

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

fourth-dimensional adjective

Examples of fourth dimension in a Sentence

Recent Examples on the Web

One popular subject of Relativity is the relationship between space and time, where time is a fourth dimension in which the three dimensions of space exist and how time passes depends entirely on your point of view. —New Atlas, 8 Dec. 2025

Importantly for the team's new measurements, something that arises from warped space-time (in the fourth dimension, remember) is that physical matter isn't the only thing affected by the warps. —Monisha Ravisetti, Space.com, 7 Aug. 2025

In other words, space-time is a conceptual model that combines the dimensions of space with a fourth dimension of time. —Madison Dapcevich, Discover Magazine, 1 Aug. 2025

While some pregnant women are strapping on a belly band and calling it a day, the billionaire voice of Smurfette is innovating into the fourth dimension, wearing a skirt that, no joke, might be…inflatable? —Elizabeth Logan, Glamour, 14 July 2025

Word History

First Known Use

1875, in the meaning defined at sense 1

Rhymes for fourth dimension

• apprehension
• comprehension
• condescension
• hypertension
• hypotension
• reinvention
• reprehension
• resuspension
• attention
• contention
• convention
• declension