According to the Book of Rhymes (Guangyun), this is an ancient form of the character for dwelling (zhai). For detailed annotations, see the section under Radical: Roof (mián), three strokes. Also, according to the Book of Rhymes (Guangyun), this is an ancient form of the character for degree or measure (du). In the Book of Changes: Drilling into the Mystery of Heaven and Earth (Yi Qiankun Zaodu), the text regarding the ancestors of Pao Xi is written with this character. For detailed annotations, see the section under six strokes. It is also used interchangeably with the character for measure (du), as in planning or calculation. In the Compilation of Rhymes (Jiyun), the character for measure (du) is sometimes written in this variant form.