means something “given to God” (deo-dandum). This was the case when a man met with his death through injuries inflicted by some chattel, as by the fall of a ladder, the toss of a bull, or the kick of a horse. In such cases the cause of death was sold, and the proceeds given to the Church. The custom was based on the doctrine of purgatory. As the person was sent to his account without the sacrament of extreme unction, the money thus raised served to pay for masses for his repose. Deodands were abolished September 1st, 1846.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894