A looter or plunderer was a type of thief who engaged in looting, the large-scale theft of goods during a time of diminished public order, such as wars, riots, or natural disasters.
Following the Cardassian withdrawal from Deep Space 9 in 2369, looters broke into the station's infirmary. (DS9: "Emissary")
Upon arriving at the Hur'q planet in the Gamma Quadrant, and the supposed located of the Sword of Kahless, Jadzia Dax's scans from orbit revealed "a series of interconnected structures and tunnels several kilometers beneath the surface." Upon hearing this, Kor relished in the fact that "that is all that remains of the Hur'q, the great plunderers of the galaxy." (DS9: "The Sword of Kahless")