Greed is a form of desire. However, it is an exaggerated form of desire, based on overexpectation. The true antidote of greed is contentment.
For a practicing Buddhist, for a Dharma practitioner, many practices can act as a kind of counterforce to greed: the realization of the value of seeking liberation or freedom from suffering, recognizing the underlying unsatisfactory nature of one’s existence, and so on. These views also help an individual to counteract greed. But in terms of an immediate response to greed, one way is to reflect upon the excesses of greed, what it does to one as an individual, where it leads. Greed leads one to a feeling of frustration, disappointment, a lot of confusion, and a lot of problems.
When it comes to dealing with greed, one thing which is quite characteristic is that although it arises from the desire to obtain something, it is not satisfied by obtaining it. Therefore, it becomes limitless or boundless, and that leads to trouble. The interesting thing about greed is that although the underlying motive is to seek satisfaction, as I pointed out, even after obtaining the object of one’s desire, one is still not satisfied. On the other hand, if one has a strong sense of contentment, it doesn’t matter whether one obtains the object or not; either way, one is still content.(p.32)
–from Healing Anger: The Power of Patience from a Buddhist Perspective by the Dalai Lama, translated by Geshe Thupten Jinpa, published by Snow Lion Publications