a murderer, esp of a political or religious leader
(Assassin) any of a secret order of Muslims who committed secret murders at the time of the Crusades
medieval Latin assassinus from Arabic ḥashshāshīn, pl of ḥashshāsh one who smokes or chews hashish. The original Assassins were members of a heterodox branch, called the Isma‘īlites, of the Shiite sect of Islam. Founded at the end of the 11th cent., they were active in Iran and Syria until the 13th cent. The word assassin was brought to Europe by crusaders. It was used in Latin texts by English writers as early as the 13th cent., and by the early 17th cent. was used in English in both its original and extended senses