What fukusa means
The fukusa is a small square of silk, typically around 27 centimeters per side, that the host folds and uses to wipe the natsume and chashaku before serving tea. The color is read as a marker of the host's school and rank, with Urasenke traditionally using red or vermilion for women and purple for men. The cloth is not meant to clean physical residue so much as to mark a transition into the formal preparation. A separate kobukusa is used by guests to handle the chawan during koicha.
Also called
Fukusa also appears as tea silk, purification cloth.