expanding universe

American  

noun

Astronomy.

1. 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.

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Etymology

Origin of expanding universe

First recorded in 1930–35

Example Sentences

“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

In 1934, Tolman published his book "Relativity, Thermodynamics, and Cosmology," inspired in part by the descriptions of an expanding universe model first proposed by Edwin Hubble in 1929.

From Salon • Feb. 2, 2023

There was no up or down in a finite but expanding universe in which even the vast, burning, dazzling, majestic sun was in a state of progressive decay that would eventually destroy the earth too.

From "Catch-22" by Joseph Heller