'assassin' definitions:

Definition of 'assassin'

(from WordNet)
noun
A murderer (especially one who kills a prominent political figure) who kills by a surprise attack and often is hired to do the deed; "his assassins were hunted down like animals"; "assassinators of kings and emperors" [syn: assassin, assassinator, bravo]
noun
A member of a secret order of Muslims (founded in the 12th century) who terrorized and killed Christian Crusaders