'Scummy' definitions:

Definition of 'scummy'

From: WordNet
adjective
Of the most contemptible kind; "abject cowardice"; "a low stunt to pull"; "a low-down sneak"; "his miserable treatment of his family"; "You miserable skunk!"; "a scummy rabble"; "a scurvy trick" [syn: abject, low, low-down, miserable, scummy, scurvy]
adjective
Covered with scum; "the scummy surface of the polluted pond"

Definition of 'Scummy'

From: GCIDE
  • Scummy \Scum"my\, a. Covered with scum; of the nature of scum. --Sir P. Sidney. [1913 Webster]