That quarter of the Milky Way Galaxy appearing to be located between 9 and 12 o'clock if the great plane of the galaxy is viewed as a clockface and the 6 o'clock position bisects the Sol system.

The Gamma Quadrant had been surveyed only remotely until the discovery of the Bajoran wormhole opened it to direct exploration -- and brought on the conflict with the quadrant's major power, the malevolent Dominion and its Founder shapeshifters, Vorta and Jem'Hadar fighters.