Prison Term
noun
A punish period of time is the time in which you are being punished in prison. This is your prison term.
けいき
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
その囚人は、十五年間の刑期を務めた後で釈放されたが、行く当てがなかった。
The convict was released after serving a fifteen-year prison term, but he had nowhere to go.