also: しらたえ
noun
Refers specifically to cloth made from the fibers of the paper mulberry (楮) tree, historically used for clothing. Now a literary or historical term.
万葉集には白妙の衣を詠んだ歌がある。
In the Man'yōshū, there are poems that sing of robes of white cloth.
noun
pure white; snow-white
Used as a poetic epithet (makurakotoba) for things associated with whiteness, such as snow, clouds, or sleeves. Not used in everyday conversation.
白妙の雪が静かに降り積もる。
The pure white snow falls and piles up quietly.
Kana spelling is sometimes used, especially in poetic or literary contexts.
Alternate kanji form using 栲, which originally referred to a type of tree whose bark was used to make cloth. Rare in modern usage.
Older reading variant, now largely replaced by しろたえ. Still encountered in classical poetry.
白 is the general word for 'white' in modern Japanese, while 白妙 is a poetic or historical term for white cloth or pure whiteness.
From 白 (shiro, 'white') + 妙/栲 (tae, 'cloth made from paper mulberry fibers'). The kanji 栲 specifically refers to the tree, while 妙 is a phonetic substitute. The reading しらたえ is an older form.