Synonyms

deep space

American

noun

space beyond the limits of the solar system.

deep space British

noun

any region of outer space beyond the system of the earth and moon

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

deep-space adjective

Etymology

Origin of deep space

First recorded in 1950–55

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.

Artemis III will stick in near-Earth orbit — closer to where the International Space Station sits as opposed to traveling into deep space like Artemis II.

From Los Angeles Times • Apr. 12, 2026

While hurtling through deep space and zipping around the Moon, the Artemis astronauts took thousands of photographs, amassing a stunning portfolio of images.

From Barron's • Apr. 11, 2026

Unlike earlier missions, Artemis is designed with longer-term goals in mind, including future crewed landings and the development of infrastructure that could support deep space exploration.

From Salon • Apr. 11, 2026

He is a deep space network mission operations engineer at the site.

From BBC • Mar. 27, 2026

We would spend hours playing pretend games about missions to deep space, or landing on Pluto.

From "Auggie & Me" by R. J. Palacio

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