Deep space

Deep space referred to more empty regions of space, between stars or galaxies.

Sector 16 (TV: Earthshock) and the fifty-fourth sector of chartered space existed in deep space. (PROSE: The Dimension Riders)

When travelling through deep space, one could experience deep space sickness. (TV: The Space Pirates) Oxygen and water were considered precious things while in deep space, as anyone having undergone space travel training would know quite well. Space Station W3 was, among other things, a stopping point for deep space ships. (TV: The Wheel in Space)

Sanctuary bases were made by humans for deep space exploration. (TV: The Impossible Planet)

A Dalek deep space cruiser was six hours away from Skaro when Davros wanted to escape the Movellans. (TV: Destiny of the Daleks)

The Eye of the Storm, a scientific research station, was in deep space. Experiments with a wormhole bomb inadvertently created a Zero Space in the area around the station, devoid of anything. (AUDIO: Zero Space)

A hypercube knocked on the TARDIS' outer door while it was in "very, very deep" space. (TV: The Doctor's Wife)

While fleeing from the Glass Woman, the Twelfth Doctor took the First Doctor's TARDIS from Antarctica in 1986 to deep space. (TV: Twice Upon a Time)