Wu Collection, Middle Volume
Radical: Sickness (bù)
16 Kangxi strokes
Page 779, Entry 17
Pronounced yi (falling tone). Same as the character meaning quiet.
As cited in the Collection of Rhymes (Jiyun) and the Orthography of Rhymes (Zhengyun), both sources define it as quiet.
From the History of the Former Han (Qian Hanshu), Biography of Imperial Relatives: She was elegant, quiet, and possessed high moral integrity.
The commentary by Shigu states: The character means quiet.
Furthermore, according to Yangzi in the Dialects (Fangyan): The character implies discernment. In the regions of Qi and Chu it is called this, while in Qin and Jin it is called di.
Also, in the Rhapsody on the Bamboo Flute (Dongxiao Fu) by Wang Bao: Its marvelous sound is pure, quiet, and profound, proceeding in order like a filial son serving his parents.
The commentary states: The character means deep and obscure.