noun
Archaic term for divination or fortune-telling. In modern Japanese, 占い (うらない) is the common word. This sense is mostly encountered in historical or literary contexts, or in the compound 卜する (ぼくする).
See also: 卜する
古代中国では、亀の甲羅を使って卜を行った。
In ancient China, they performed divination using turtle shells.
「卜する」は、占うという
noun
choosing; deciding
Rare, archaic sense of choosing or settling something, possibly by divination. This usage is not productive in modern Japanese and appears mainly in classical texts.
古い文献では、吉日を卜するという表現が見られる。
In old documents, you can see the expression 吉日を卜する, meaning to choose an auspicious day.
卜する is an old way of saying 'to divine' or 'to tell fortunes'.