BJA vs government agency

BJA and government agency both are nouns.

Word	Noun	Adjective	Verb	Adverb
BJA	Yes	No	No	No
government agency	Yes	No	No	No

As nouns, government agency is a hypernym of BJA; that is, government agency is a word with a broader meaning than BJA:

BJA: the bureau in the Department of Justice that assists local criminal justice systems to reduce or prevent crime and violence and drug abuse
government agency: an administrative unit of government

Other hypernyms of BJA include agency, authority, bureau, federal agency, office.

BJA (noun)	government agency (noun)
the bureau in the Department of Justice that assists local criminal justice systems to reduce or prevent crime and violence and drug abuse	an administrative unit of government