Chen Collection, Upper Volume
Radical: Moon (yuè)
Kangxi Strokes: 7
Page 975, Entry 15
Tang Rhyme (Tangyun), Collected Rhymes (Jiyun), and Rhyme Meeting (Yunhui) state it is pronounced niu (falling-rising tone).
Explaining Graphs and Analyzing Characters (Shuowen) states: On the first day of the lunar month, when the moon appears in the east, it is called suo-nu. The character is formed by the radical for moon with a phonetic component. Note: The character is not derived phonetically from the interior element; it should be derived from the meat element to obtain the proper sound. Jade Chapters (Yupian) writes it as a variant form (nu), while current versions of Explaining Graphs and Analyzing Characters (Shuowen) write it as nu, which is an error introduced during the transmission of the text.
Broad Rhymes (Guangyun), Collected Rhymes (Jiyun), and Rhyme Meeting (Yunhui) state it is pronounced niu (falling-rising tone).
Explaining Graphs and Analyzing Characters (Shuowen) states: Nu is when, on the first day of the lunar month, the moon appears in the east; this is called suo-nu.
Xu says: This means the moon is moving too quickly.
Also, Collected Rhymes (Jiyun) states it is pronounced ne (entering tone). Wu-nu describes a fat or obese appearance.
Additionally, Corrected Meanings (Zhengtong) states: The kidney of a fur seal is called wu-nu-qi.
Also, Broad Rhymes (Guangyun) and Collected Rhymes (Jiyun) state it is pronounced nv (entering tone). The meaning is the same.