One-shouldered kimono

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[Special costume]
In "Taiheiraku," the performers wear armor that is said to have been the costume used in "The Tale of the King of Qin Breaking the Battle of the Battle of Qin," but over the robe and hakama they also wear shoulder pads, shoulder rests, belt rests, a fishing belt, fish bags, gauntlets, shin guards, armor, and a helmet, and they also wear swords and hold spears.
[Wearing style]
There are three styles of Bugaku costume: nugazu (no lining), katakatanugi (one-shoulder lining), and morokatanugi (all shoulder lining). In nugazu, the lining is left as is, in one-shoulder lining it is only the right shoulder, and in morokatanugi, both shoulders are removed, but in Ban-e costumes there are no morokatanugi. In Azuma Asobi, Kishunraku, Shirahama, etc., the costume changes from nugazu to one-shoulder lining midway through the dance.

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

Source | Heibonsha World Encyclopedia 2nd Edition | Information

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［特殊な装束］
　《太平楽》には《秦王破陣楽（じんのうはじんらく）》の装束であったといわれる甲冑装束を用いるが，袍，袴の上に肩当て，肩喰（かたくい），帯喰（おびくい），胡簶（やなぐい），魚袋（ぎよたい），籠手（こて），脛当，鎧，兜を着装し，太刀を佩き鉾を持つ。
［着装の形態］
　舞楽装束の着装には不袒（ぬがず），片肩袒（かたかたぬぎ），諸肩袒（もろかたぬぎ）の3態があり，不袒はそのまま，片肩袒は右肩に限り，諸肩袒は左右ともぬぐが，蛮絵装束には諸肩袒はない。東遊や《喜春楽》《白浜》等は舞の途中で不袒より片肩袒となる。…

※「片肩袒」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