From thanatos to kill (literally or figuratively) -- become dead, (cause to be) put to death, kill, mortify.
see GREEK thanatos
1. properly, to put to death: τινα, Matthew 10:21; Matthew 26:59; Matthew 27:1; Mark 13:12; Mark 14:55; Luke 21:16; 2 Corinthians 6:9; 1 Peter 3:18; passive, by rhetorical hyperbole, to be in the state of one who is being put to death, Romans 8:36.
2. metaphorically,
a. to make to die i. e. destroy, render extinct (something vigorous), Vulg.mortifico (A. V. mortify): τί, Romans 8:13.
b. passive with the dative of the thing, by death to be liberated from the bond of anything (literally, to be made dead in relation to; cf. Winers Grammar, 210 (197); Buttmann, 178 (155)): Romans 7:4.