Spoiler warning: Plot and/or ending details follow.
Refrigeration is the process of cooling a space to a lower temperature by transferring the heat out of the space.
Refrigeration is often done to preserve foodstuffs until they could be consumed. Prior to the advent of stasis technology refrigeration was also used to help preserve deceased individuals until they could be properly disposed of through burial, cremation, or other methods. Some cold weather species, such as the Breen, made use of refrigerated suits to be able to operate in standard Class M environments.