Lowball

The word Lowball has several senses:

Lowball (poker) is a poker variant in which traditional hand values are reversed so that the lowest-valued hand wins. Lowball usually implies five-card draw played for low, but there are several interpretations of this idea.
A class of alcoholic beverage: an unmixed drink served on ice or water in a short glass (a back-formation from highball).
As a verb, to underestimate or understate a price, for example in bargaining for a purchase.