third dimension

American  

noun

1. the additional dimension by which a solid object is distinguished from a planar projection of itself or from any planar object.

2. something that heightens the reality, vividness, or significance of a factual account, sequence of happenings, etc..

   The illustrations added a third dimension to the story.

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third dimension British  

noun

1. the additional dimension by which a solid object may be distinguished from a two-dimensional drawing or picture of it or from any planar object

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Etymology

Origin of third dimension

First recorded in 1855–60

Example Sentences

And I just started writing songs, and I found that it was like a third dimension, sort of “Twilight Zone”-style, that I could go to and exit my body entirely.

From Los Angeles Times • Dec. 1, 2025

Van der Waals materials are made up of strongly bonded 2D layers that are bound in the third dimension through weaker van der Waals forces.

From Science Daily • May 1, 2024

"There is this third dimension of space which offers so much more exciting information and perspective that we tend to ignore."

From Salon • Dec. 25, 2022

Adi Segalprojects a gold-emblazoned geometric screen print into the third dimension with artful folding.

From Washington Post • Mar. 25, 2022

In a two-dimensional universe, curved through a third dimension, there is no center—at least not on the surface of the sphere.

From "Cosmos" by Carl Sagan