Meaning: Money paid for treachery, betrayal, murder.
Coverdale
Matthew 27:6 "It is not lawful for us to put it into the Gods chest for it is blood-money."
Matthew 27:5-6
And he cast down the pieces of silver in the temple, and departed, and went and hanged himself. [6] And the chief priests took the silver pieces, and said, It is not lawful for to put them into the treasury, because it is the price of blood.