Assassination is the targeted killing of a high-profile person. An added distinction between assassination and other forms of killing is that the assassin (one who performs an assassination) usually has an ideological or political motivation, though many assassins (especially those not part of an organization) also demonstrate insanity. Other motivations may be money (contract killing), revenge, or a military operation.
The assassination euphemism targeted killing (extrajudicial execution) is also used for the government-sanctioned killing of opponents. 'Assassination' itself, along with terms such as 'terrorist' and 'freedom fighter', may in this context be considered a loaded term, as it implies an act in which the proponents of such killings may consider them justified or even necessary.
Assassination may also be used as a form of hyperbole, as in the phrase character assassination, meaning an attempt to impugn another's character, and thus kill, or "assassinate" his reputation and credibility.