Temecklia was an orange K-type star located in the Alpha Quadrant, not far from the borders of the Tzenkethi Coalition. Its planetary system included a number of worlds, at least one of which, Temecklia II, was inhabited. (Star Trek Star Charts; TCT: "Iron and Sacrifice")
The disease known as the Temecklian virus presumably originated in this system. (DS9: "For the Cause")