continuance vs time period

continuance and time period both are nouns.

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

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

Other hypernyms of continuance include period, period of time.

continuance (noun)	time period (noun)
the act of continuing an activity without interruption	an amount of time
the property of enduring or continuing in time
the period of time during which something continues