(coexisting on another dimensional plane)
The Terran Imperial credit was the monetary unit of the Terran Empire.
In 2267, in an attempt to gain release from USS Enterprise's brig, the mirror universe Kirk switched tactics from his earlier threats, instead offering a bribe to prime universe Spock in "credits" and promising that the Vulcan could become a rich man. Mirror Kirk also mentioned the possibility of giving him a command of his own, if Spock so desired. (TOS: "Mirror, Mirror")