anti-federalists

noun

1. U.S. History. a member or supporter of the Antifederal party.
2. (lowercase) an opponent of federalism.

noun

1. US history a person who opposed the ratification of the Constitution in 1789 and thereafter allied with Thomas Jefferson’s Antifederal Party, which opposed extension of the powers of the federal Government
2. (often not capital) any person who opposes federalism