lifetime vs time period

lifetime and time period both are nouns.

Word	Noun	Adjective	Verb	Adverb
lifetime	Yes	No	No	No
time period	Yes	No	No	No

As nouns, time period is a hypernym of lifetime; that is, time period is a word with a broader meaning than lifetime:

lifetime: the period during which something is functional (as between birth and death)
time period: an amount of time

Other hypernyms of lifetime include period, period of time.

lifetime (noun)	time period (noun)
the period during which something is functional (as between birth and death)	an amount of time