meaning of scum
1.  The extraneous matter or impurities which rise to the surface of liquids in boiling or fermentation, or which form on the surface by other means; also, the scoria of metals in a molten state; dross. 
2.  refuse; recrement; anything vile or worthless. 
3.  To take the scum from; to clear off the impure matter from the surface of; to skim. 
4.  To sweep or range over the surface of. 
5.  To form a scum; to become covered with scum.  Also used figuratively. 
6.  a film of impurities or vegetation that can form on the surface of a liquid
						 
Related Words
scum | scum bag | scumber | scumble | scumbled | scumbling | scummed | scummer | scumming | scummy |
