scum bag

Noun
  1. a person who is deemed to be despicable or contemptible
    • only a rotter would do that
    • kill the rat
    • throw the bum out
    • you cowardly little pukes!
    • the British call a contemptible person a `git'
scum bag
A man in a dark alley is known as a scum bag by the local shopkeepers.