小袖

Compound of 小 (ko, “small”) +‎ 袖 (sode, “sleeve”). Named in contrast to 大袖(おおそで) (ōsode, literally “large sleeve”), a type of formal robe (reifuku) worn in the Imperial court or during ceremonies.[1]

小袖 (sense 4): a woman’s short-sleeved kosode

小(こ)袖(そで) • (kosode) 

1. (historical) [a. 12th century] a long garment with narrow sleeves worn as underwear by upper-class people
2. [12th to 18th century] a garment worn under a ceremonial dress (reifuku)
3. [from 16th century] a short-sleeved padded silk robe, worn under a kimono

   Synonym: 丸物 (marumono)

4. a Japanese robe similar to a kimono

In reference under-clothing, 小袖 is attested from the Heian period. It originally referred to white silk robes worn by women or men in layers, with dyed colors and other decoration developing later. By the Azuchi–Momoyama period, it was common for women and men to wear an 帯(おび) (obi) sash over the outermost kosode, leading to development of the contemporary 着物(きもの) (kimono).[1]

• 礼服(れいふく) (reifuku, “formal dress; ceremonial dress”)
• 羽織(はおり) (haori): a short coat for formal kimono
• 水干(すいかん) (suikan): a kimono tunic
• 袴(はかま) (hakama): traditional Japanese trousers