outerspace

WordReference Random House Learner's Dictionary of American English © 2026

ˈout•er ˈspace, n. [uncountable]

1. Astronomy space beyond the atmosphere of the earth.
2. Astronomy space beyond the solar system;
   deep space.

WordReference Random House Unabridged Dictionary of American English © 2026

out′er space′, 

1. Astronomy space beyond the atmosphere of the earth.
2. Astronomy See deep space. 
• 1875–80

Collins Concise English Dictionary © HarperCollins Publishers::

outer space noun

1. (not in technical usage) any region of space beyond the atmosphere of the earth