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as·sas·sin (ə-săsĭn)
1. One who murders by surprise attack, especially one who carries out a plot to kill a prominent person.
2. Assassin A member of a militant subgroup of Ismailis that in the 11th, 12th, and 13th centuries carried out political assassinations directed especially against Seljuk rule.
3. A game in which players eliminate other players by tagging them with an innocuous object, as a sock, rubber band, or pellet from a paintball gun, until only one player remains.

[French, from Medieval Latin assassīnus, from Arabic aššāšīn, pl. of aššāš, hashish user, from ašīš, hashish; see HASHISH.]

Word History: The history of the word assassin shows how legends can influence the development of words as powerfully as facts. European legends about a murderous, drug-crazed sect called the Assassins grew up around the Nizaris, a group of Ismaili Shi'ite Muslims that held strongholds in Iran and Syria from the 11th to the 13th century. The Nizaris opposed the rule of the Seljuk dynasty and the Abbasid caliphs, who were Sunni and regarded the Nizaris as unorthodox outcasts. Sunni accounts of the Nizaris accused them of all sorts of irreligious practices, and one term of abuse applied to the Nizaris was the Arabic word aššāšīn, meaning "hashish users." Reliable sources, however, offer no evidence of hashish use by Nizaris. The Nizaris mounted resistance to this persecution, and one of their most formidable weapons against the Seljuks was the threat of sudden execution by secret agents. Attacks on several leaders among the Crusaders were also attributed to Nizari agents. When the Crusaders returned to Europe, they embellished upon what they had heard about the Nizaris from the group's enemies and told sensational stories about the aššāšīn or Assassins. Marco Polo spun a tale of how young Assassins were given a potion and made to yearn for paradisetheir reward for dying in actionby being given a life of sensual pleasure before their secret missions. As the legends spread, the word aššāšīn passed through Italian and French and appeared in English as assassin in the 1500s, already with meanings like "treacherous killer."

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.

Indo-European & Semitic Roots Appendices

    Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

    Indo-European Roots

    Semitic Roots

    The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.