A single-layer, absorbent robe worn during or after a bath (archaic term; similar to a yukata or bath-robe).
温泉で湯帷子を羽織り、露天風呂の縁に座った。
Wearing a yukatabira, I sat on the edge of the open-air bath at the hot spring.
昔の女性は入浴後に湯帷子をまとって着替えた。
In the past, women would wrap themselves in a yukatabira after bathing to change clothes.