Hai Collection, Upper Volume
Radical: Bone (gǔ)
髃
Kangxi strokes: 19
Page 1450, Entry 17
Pronounced yu. Identical to the character meaning the junction of the collarbone and the shoulder.
According to the Explaining Graphs and Analyzing Characters (Shuowen Jiezi), it refers to the area at the front of the shoulder.
In the Commentary on the Book of Odes (Shijing) section Small Odes (Xiaoya), specifically the passage regarding the Great Cook, it describes an arrow entering from the lower left abdomen and exiting at the right front of the shoulder, which is described as the superior method of butchering.
According to the Explanatory Text (Shiwen), the character is sometimes written in the variant form 腢. It refers to the space between the two bones at the front of the shoulder.
Pronounced ou. Also pronounced wei. Also pronounced the same. The meaning remains the same.