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As*sas"sin (#), n. [F. (cf. It. assassino), fr. Ar. hashishin one who has drunk of the hashish. Under its influence the Assassins of the East, followers of the Shaikh al-Jabal (Old Man of the Mountain), were said to commit the murders required by their chief.]

One who kills, or attempts to kill, by surprise or secret assault; one who treacherously murders any one unprepared for defense.