Onchugen - Ochugen

...It is said that this name comes from the fact that among servants, they were below the samurai and above the zoshiki (minor servants), that is, they were in the middle of the two ("Shikisou" and "Teijo Zakki"); however, there are also examples where they are written in the order of samurai, zoshiki, and nakama ("Hojo Shigetoki Kakun"). In the Kamakura and Muromachi periods, nakama of the samurai were described as "carrying the lord's bow, arrows, sword, etc., and accompanying the lord, and also performing guard duties" ("Sokyo Shokusho"), or "wearing a folded eboshi hat and a komusubi hat, a large shawl over a naoshi garment, and a large hakama over a oguchi" ("Tamakatsuma" and others), and they were called onakama and also served as messengers for the lord's enforcement. While samurai (tonobara, wakato, kasemono, etc.) had surnames, nakama were described as "those without surnames" ("Kobayakawa Family Documents").

*Some of the terminology explanations that refer to "Onakama" are listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…従者のうち侍の下で雑色（ぞうしき）(小者)の上，つまり両者の中間に位置するところから，この名があるともいわれるが(《四季草》《貞丈雑記》)，侍，雑色，中間の順に記す例もみられる(《北条重時家訓》)。鎌倉･室町期の武家の中間は〈主人の弓･箭･剣等を持ちて御供に候し，また警護等のことをつとむ〉(《相京職鈔》)とか，〈折烏帽子に小結して，直衣に大帷をかさね，袴に大口をかさねて著るが中間〉とされ(《玉勝間》ほか)，御中間といわれて領主の強制執行などの使者もつとめた。侍(殿原（とのばら）･若党･かせ者など)が名字をもつのにたいして，中間は〈名字なき者〉とされた(《小早川家文書》)。…

※「御中間」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