Si Collection, Middle Volume. Radical: Fire (huǒ). Kangxi stroke count: 13. Page 677, Entry 18.
Broad Rhymes (Guangyun): Pronounced sha. Collected Rhymes (Jiyun) and Orthographic Rhymes (Zhengyun): Pronounced sha.
Broad Rhymes (Guangyun): A vulgar form of the character for to kill (sha). Comprehensive Discussions in the White Tiger Hall (Baihu Tong): Among the Five Sacrifices, the spring wood divinity governs death, thus one performs the sacrifice using that which it overcomes. Furthermore, why does the taste of metal manifest as pungent? Because the west governs the killing and wounding that brings things to completion, and pungency is the agent of that killing and wounding. It is similar to how the five flavors require pungency to attain their mature, distinct character.
Also, Collected Rhymes (Jiyun): Pronounced jie. It is a variant of the character for to kill (sha). Orthographic Rhymes (Zhengyun): Pronounced shai. See the note for the character for to kill (sha) under the Weapon (shu) radical.