federal savings bank vs FSB

federal savings bank and FSB both are nouns.

Word	Noun	Adjective	Verb	Adverb
federal savings bank	Yes	No	No	No
FSB	Yes	No	No	No

As nouns, federal savings bank and FSB are synonyms defined as:

federal savings bank (noun)	FSB (noun)
a federally chartered savings bank	a federally chartered savings bank
	the internal counterintelligence agency of the Russian Federation and successor to the Soviet KGB; formerly led by Vladimir Putin