Assassination is the murder of a prominent person or political figure by a surprise attack, usually for payment or political reasons.

An assassination may be prompted by religious, ideological, political, or military motives; it may be carried out for the prospect of financial gain, to avenge a grievance, from the desire to acquire fame or notoriety (that is, a psychological need to garner personal public recognition), from the wish to form some kind of "relationship" with a public figure, or from the desire (or at least the willingness) to be killed or commit suicide in the act.

Read more about Assassination:  Etymology, Psychology, Targeted Killing