Real Dictionary

federal
A federal country or system of government is one in which the different states or provinces of the country have important powers to make their own laws and decisions.

federal in American English
a Federalist
of or formed by a compact; specif., designating or of a union of states, groups, etc. in which each member agrees to subordinate its governmental power to that of the central authority in certain specified common affairs
adjective: pertaining to or of the nature of a union of states under a central government distinct from the individual governments of the separate states
noun: an advocate of federation or federalism

federal in British English
adjective: of or relating to a form of government or a country in which power is divided between one central and several regional governments
adjective: of or relating to the Federalist party or Federalism
noun: a supporter of federal union or federation
noun: a supporter of the Union government during the American Civil War