first day cover

...An institution that handles the so-called three postal services, such as mail, postal savings, postal money orders, postal transfers, postal life insurance, and postal pensions, through counters, etc. According to the Postal Ministry Establishment Act enacted in 1948, it is stipulated that it is responsible for the operational business among the business handled by local post offices. When the postal service was established in 1871 (Meiji 4), post offices and postal handling offices were established, and it was in 1875 that they came to be called post offices. In 1873, the existing post offices were made into first-class post offices, and 270 of the postal handling offices were selected and changed to second-class, second-class, third-class, and fourth-class post offices, and the job of the head of each postal office was made into the handling office. ...

*Some explanations of terms that refer to "first day cover" are listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…郵便，郵便貯金，郵便為替，郵便振替，簡易生命保険，郵便年金など，いわゆる郵政三事業の業務を，窓口等を通し具体的に取り扱う機関。1948年制定の郵政省設置法によれば，地方郵政局の取扱い業務のうちの現業関係業務を担当するものと定められている。郵便事業が創業された1871年(明治4)当時は，郵便役所と郵便取扱所が設置されており，これが郵便局と呼ばれるようになったのは，75年のことである。1873年に従来の郵便役所を一等郵便役所とし，郵便取扱所のうちから270ヵ所を選んで，二等から四等までの郵便役所に改め，その長である職務を取扱役とした。…

※「first day cover」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報