Bipartisan refers to an issue, plan or program that is supported by two political parties from opposite ends of the political spectrum. For example, a bill supported by members of both the Republican and Democrat parties in Congress is bipartisan.
Bipartisan applies both to agendas that are initially supported by both parties and to agendas that are supported by both parties after a compromise is agreed upon in any political arena with two strong opposing political parties. For some issues, party leaders develop bipartisan resolutions only after they feel their own party's ideology is better served. Bipartisan solutions to political problems are often necessary for bills to pass through Congress successfully.