A Governmentard is one who legislates poorly or not at all, and the laws he/she puts into effect(or fails to put into effect) tend to harm the governed.
Alternately, the governmentard can be one who legislates solely to keep office, or keep others from staying in office. The best way to be sure that you have identified a governmentard is to determine whether or not they have any useful purpose in government, whatsoever. If they are useless or detrimental, then you have yourself a prime example of a governmentard.
Example 1: The House Republicans in July 2011 are total governmentards- their proposed legislation which they have artificially connected to the debt ceiling, which they can't even agree upon, threatens the financial future of the globe, and everyone knows their sole purpose is to keep Obama from being reelected.
Example 2: John Boner(a fictitious character not to be confused with anyone in office, past or present) is a prime governmentard- he will damage our country just so the Republican party can inherit the earth. Have they considered what it is that they will inherit?