noun
period of stay; authorized length of stay; duration of stay
Refers to the legally permitted period a foreign national may remain in a country, commonly used in immigration and visa contexts.
在留期間が切れる前に更新手続きをしてください。
Please apply for renewal before your period of stay expires.
このビザの在留期間は90日です。
The authorized length of stay for this visa is 90 days.
Compound of 在留 (ざいりゅう, 'staying in a foreign country') and 期間 (きかん, 'period').