Greed is an uncontrolled longing for increase in the acquisition or use of material gain (be it food, money, land, or animate/inanimate possessions); or social value, such as status, or power. Greed has been identified as undesirable throughout known human history because it creates behavior-conflict between personal and social goals.
"Earth provides enough to satisfy every man's needs, but not every man's greed." -- Mahatma Gandhi
Charity and Generosity
If you wish to suppress Greed, do charity. Greed is a desire of taking, so to counter it start giving, start being generous.