(archaic) the blood of one's severedneck (after one's head has been chopped off for showing defiance); to be ready and willing to die (for what one believes in)
Dong Zhuo, you villainousscoundrel! You dare carry out a scheme which deceives heaven. I should stain you with the blood of my (severed) neck (rather than submit, and live in tyranny)!
Usage notes
The use of this term implied that one was ready and willing to die for what one believed in