noun
poste restante; general delivery; counter collection
A postal service where mail is held at a post office for the recipient to collect, rather than being delivered to an address.
旅行中は郵便物を局留めにしてもらった。
While traveling, I had my mail held at the post office for collection.
局留めで送れば、
If you send it by poste restante, you can receive it reliably.