Ring head - Kanto

…The distinctive feature of a tachi is that it is hung from the waist with the blade facing down, with a foot metal fitting attached to the sheath and an obitori strap. From the Nara period to the early Heian period, it was written as daitachi or yokotachi and read as tachi, but in later times it was usually written as tachi. The maker's signature on the blade is usually inscribed on the front of the sword, so even without the exterior, it is easy to distinguish it from the uchigatana, which is worn on the waist with the blade facing up. Tachi types are broadly divided into ceremonial swords for ceremonies and military swords for battle, but as new styles are constantly developing, the old styles for battle have become formal and have become ceremonial swords. …

*Some of the terminology explanations that mention "ring head" are listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…鞘（さや）に足金物（あしがなもの）を設け，帯取（おびとり）の緒をつけて，刃を下に向けて腰につるすのを太刀の特色とする。奈良時代から平安時代の初期には大刀または横刀と書いて〈たち〉と読ませ，後世は太刀と書くのが常である。太刀身も作銘（さくめい）は佩表（はきおもて）に入れるのを常とするから，外装がなくとも，刃を上に向けて腰に差す打刀（うちがたな）の類とは容易に識別することができる。太刀の種類は礼典用の儀仗（ぎじよう）と軍陣用の兵仗（ひようじよう）に大別されるが，つねに新様式の発達にともなって，軍陣用も旧様式は形式的となり，儀仗化している。…

※「鐶（環）頭」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