swan's-down
(swänz′do̵un′, swônz′-)
noun
- the soft, fine under-feathers, or down, of the swan, used for trimming clothes, etc.
- a soft, thick fabric of wool and silk, rayon, or cotton, used for making baby clothes, etc.
- a cotton fabric with a satin weave and a heavy napped finish
- a very soft cotton flannel
See swan's-down in American Heritage Dictionary 4
also swans·down
noun- The soft down of a swan.
- A soft woolen fabric used especially for baby clothes.
- Flannelette.