masc. proper name, from Old French rousel, diminutive of rous "red," used as a personal name. See russet. Also a name for a fox, in allusion to its color. Compare French rousseau, which, like it, has become a surname. Russell's Paradox, "the set of all sets that do not contain themselves as elements," is named for Bertrand Russell (1872-1970) who is said to have framed it about 1901.
in the philosophical sense of "voluntary agency" (embracing desire and volition), 1836, from Latin conationem (nominative conatio) "an endeavoring, effort," noun of action from past participle stem of conari "to endeavor, to try," from PIE *kona-, from root *ken- "to hasten, set oneself in motion" (see deacon).
initialism (acronym) from shit out of luck (though sometimes euphemised), 1917, World War I military slang. "Applicable to everything from death to being late for mess" [Russell Lord, "Captain Boyd's Battery, A.E.F.," c. 1920]