formerly in English law, "a personal chattel which, having been the immediate cause of the death of a person, was forfeited to the Crown to be sold and the money applied to pious uses," 1520s, from Anglo-French deodande (late 13c.), from Medieval Latin deodandum, from Deo dandum "a thing to be given to God," from dative of deus "god" (from PIE root *dyeu- "to shine," in derivatives "sky, heaven, god") + neuter gerundive of dare "to give" (from PIE root *do- "to give"). Abolished 1846.
Thus, if a cart ran over a man and killed him, the cart was by law forfeited as a deodand, and the coroner's jury was required to fix the value of the forfeited property. The pious object of the forfeiture was early lost sight of, and the king might and often did cede his right to deodands within certain limits as a private perquisite. [Century Dictionary]