expiration

n. /ˌekspəˈreɪʃn/ B2

期满；到期

The ending of the time when something is valid.

仙境例句

The Dormouse promised to stay awake for one whole minute; at its expiration, it was asleep again.

睡鼠保证整整一分钟不睡觉；一分钟期满，它又睡着了。