Scum
Scum was a slang term for a reprehensible person. 

The Clanton gang was described as scum by Morgan Earp. ()

Odo was described as scum while visiting Quark's in 2369. ()

Aamin Marritza, described the prisoners at Gallitep labor camp, while impersonating Gul Darhe'el, as Bajoran scum or spineless scum. ()

Zolan believed that Rugal's Bajoran parents referred to him every day as "Cardassian scum". ()
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