expanding universe

American

noun

Astronomy.

a concept or representation of the universe, based on the observed redshifts of distant galaxies, in which the galaxies are assumed to be receding from each other at a speed proportional to their separation as a result of the expansion of the universe.

Etymology

Origin of expanding universe

First recorded in 1930–35

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

“In the quickly expanding universe of cases involving sanctions for the misuse of artificial intelligence, this case is a notorious outlier in both degree and volume,” Clarke wrote.

From Los Angeles Times • Mar. 27, 2026

Radiation in the expanding universe gradually lost energy as its wavelengths stretched with spacetime.

From Science Daily • Dec. 7, 2025

He said the company's order portfolio was strong and fully booked well into 2025, but the company wanted to test this expanding universe.

From Reuters • Oct. 14, 2023

A central part of the updated theory has to do with dark energy, a mysterious, not-fully-understood aspect of the universe that is thought to be the driving force behind our expanding universe.

From Salon • Feb. 2, 2023

Physicists have theorized that we live in an infinite and infinitely expanding universe, and that everything in it will eventually repeat.

From "We Are the Ants" by Shaun David Hutchinson

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023