The American Heritage® Dictionary of the English Language, 4th Edition
adj. Put to death. Often used in combination: fresh-killed meat.
adj. Of, relating to, or containing microorganisms or infectious agents that have been inactivated so as to be incapable of causing infection: a killed virus; killed vaccines.
""To think, if you had only told your friends of the errand, and of the plans you had made for reaching the presence of the czar, that it would have succeeded and you would have killed him -- _killed him_.""