Haori

The Haori (羽織^?) is a traditional Japanese sort of hip- or thigh-length kimono-like jacket, worn over a kosode.

The haori does not close like the yukata, but is worn open or kept closed by a string that connects the lapels. During the Sengoku period, sleeveless haori were worn over the armour, like the tabard was in Europe. During the Edo period, economic growth allowed the middle class to afford the haori, yielding laws against ostentatious display of wealth by all but the warrior caste; this in turn gave birth to discreet haori designs with lavishly decorated lining.

...
Wikipedia