"Christmas tree" bill
A "Christmas tree bill" is informal nomenclature for a bill on the Senate floor that attracts many, often unrelated, floor amendments, or riders. The amendments which adorn the bill may provide special benefits to various groups or interests.
An example is the National Defense Authorization Act; since the bill is a must-pass issue, as it provides for funding for Operation Iraqi Freedom, members of the Democratic party have tried to tag the bill with various other amendments supporting the homosexual agenda. Bills that would be politically dangerous for members of Congress to be on record as voting against are thus especially likely to become "Christmas tree" bills.
-  US Senate Reference