Hello, 此時的while為名詞用法 意思是一段時間，通常指短的一段時間：a period of time, especially a short one 用法通常是a ＋ while in a while沒多久之後、很快 ex: Mr. Thomas will arrive in a while. (Mr. Thomas很快就會到。) for a while (持續)一段時間 ex: At last, he could relax for a while. (終於，他可以休息一會兒了。) ex: She had stayed here for a while yesterday. (昨天她在這待了一會兒。) Hope this helps.
