A postal delivery worker — a person who delivers mail (gender-neutral term).
郵便配達員が毎朝手紙を届けてくれる。
The postal delivery worker brings letters every morning.
昨日、郵便配達員から荷物を受け取り、サインをした。
Yesterday I received a package from the postal delivery worker and signed for it.
郵便配達員は雨の日でも配達を続けることが多い。
Postal delivery workers often continue delivering even on rainy days.