Period, Term, Interval
noun
A period of time interval is still a period or interval of time.
きかん
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
レンタル期間は十日間です。
The rental period is ten days.
今週はテスト期間中です。
This week is the test period.
このジーンズ、今なら期間限定で安いですよ。
This pair of jeans is cheap for a limited time now.