1610s, from past participle stem of Medieval Latin assassinare (see assassin). "Assassinate means to kill wrongfully by surprise, suddenly, or by secret assault" [Century Dictionary]. Of reputations, characters, etc., from 1620s. Related: Assassinated; assassinating.

"act of assassinating," c. 1600, noun of action from assassinate (v.). Earlier was assassinment (1570s).

early 15c., "bring to an end," from Latin terminatus, past participle of terminare "to mark the end or boundary," from terminus "end, limit" (see terminus). Intransitive sense of "to come to an end" is recorded from 1640s; meaning "dismiss from a job" is recorded from 1973; that of "to assassinate" is from 1975. Related: Terminated; terminating.

1798 in reference to French history, a participant in the massacre by the mob of the political prisoners in Paris, Sept. 2-5, 1792. In French, Septembriseur, hence English Septembriser (1797). Hence also septembrize "assassinate while in custody" (1793).

Roland writes indignant messages, in the name of Order, Humanity and the Law; but there is no Force at his disposal. Santerre's National Force seems lazy to rise : though he made requisitions, he says,—which always dispersed again. Nay did not we, with Advocate Maton's eyes, see "men in uniform" too, with their "sleeves bloody to the shoulder"? Pétion goes in tricolor scarf; speaks "the austere language of the law:" the killers give up, while he is there; when his back is turned recommence. [Carlyle, "The French Revolution"]