In Russia's case, I'm pretty sure it's a bunch of republics within the country that technically govern each other but aren't sovereign, I can see where that came from since the USSR was literally just a bunch of self governing republics uniting under the common goal of socialism (it's in the name). Hence why Russia calls itself today the Russian Federation.
As for Germany, well... Federated Republic of Germany. I'd assume its regions are very similarly self governing, they just don't call themselves republics here.
There's the Swiss Confederation. Not sure what the "con-" prefix means.
For Germany, the Federated part came from the three Allied zones that came together to form West Germany. Each zone would check and govern each other but weren't sovereign. Then East Germany was added to form the Germany we know today.
With Switzerland, Confederation means each part of the country came together voluntarily. Membership in a confederation is voluntary while not necessarily so in a federation.
To explain it easier for an American, the thirteen colonies came together in a confederation during the revolutionary war, united under specific circumstances but still separate. Once the constitution passed and the USA was officially formed the states switched from a Confederation to a Federation. This is also why the Confederacy is the Confederacy, the states voluntarily banded together to revolt against the Union.