ෆෙඩරල් රාජ්යය, ෆෙඩරේෂන, සන්ධීය රාජ්ය, එක්සත් රාජ්යය ( En:'federal state) යන විවිධ නම් වලින් මෙය හැඳින්වේ. මේවා අර්ධ ස්වයං පාලන ප්රාන්ත රාජ්ය හෝ ප්රදේශ මධ්යම ආණ්ඩුවක් මගින් දේශපාලනමය සංගමයකට (political union) එක්සත් වීමෙන් ( united ) සෑදුනු ස්වෛරීය රාජ්යවේ. In a federation, the self-governing status of the component states is typically constitutionally entrenched and may not be altered by a unilateral decision of the central government.
↑The USSR was a federation according to the letter of its constitution, but, at least until its final years in the late eighties and early nineties of the 20th century, its governance was highly centralised in practice. See: Soviet Union section.
↑The Socialist Federal Republic of Yugoslavia was officially proclaimed in 1963. Prior to this, the communist Yugoslav state was named Democratic Federal Yugoslavia in 1943 and then Federal People's Republic of Yugoslavia in 1946. See: Socialist Federal Republic of Yugoslavia.