One of the three characters (無, 无, 亡) that have historically been used to represent the word "no, not any". First attested in the Warring States period; used interchangeably with 無 until the Tang dynasty. Readopted by the PRC in 1956.
The origin of this character is unknown. Probably an ancient variant form of either 元, 天 or 堯. This character must not be confused with 旡.