It means “white heron” (egret).
It is a floor position in which one leg is raised or suspended, recalling the “heron” stances of martial arts.
It can be used from a seated position or starting from standing.
Important: in these positions the pelvis must not be thrown off balance, so you will probably need to raise the leg much less than you imagine, to keep the figure within a safe range and looking fluid and natural.
The term combines the characters 白 (shira), meaning “white”, and 鷺 (sagi), meaning “heron”.
The white heron has a special symbolism in Japan, related to purity and majesty.
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