fast track vs agency

fast track and agency both are nouns.

Word	Noun	Adjective	Verb	Adverb
fast track	Yes	No	No	No
agency	Yes	No	No	No

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

fast track: a rapid means of achieving a goal
agency: to have the ability to produce a particular effect or achieve an end

Other hypernyms of fast track include means, way.

fast track (noun)	agency (noun)
a rapid means of achieving a goal	to have the ability to produce a particular effect or achieve an end
	an administrative unit of government
	a business or organization that provides a particular service, especially the mediation of transactions between two parties
	the state of serving as an official and authorized delegate or agent
	the state of being in action or exerting power