fast lane vs life-style

fast lane and life-style both are nouns.

Word	Noun	Adjective	Verb	Adverb
fast lane	Yes	No	No	No
life-style	Yes	No	No	No

As nouns, life-style is a hypernym of fast lane; that is, life-style is a word with a broader meaning than fast lane:

fast lane: a hectic and pressured lifestyle often characterized by recklessness or dissipation
life-style: a manner of living that reflects the person's values and attitudes

Other hypernyms of fast lane include life style, lifestyle, modus vivendi.

fast lane (noun)	life-style (noun)
the traffic lane for vehicles that are moving rapidly	a manner of living that reflects the person's values and attitudes
a hectic and pressured lifestyle often characterized by recklessness or dissipation