Assassination is the murder of an individual; usually a political or famous figure. An added distinction between assassination and other forms of killing is that an assassin usually has an ideological or political motivation, though many assassins (especially those who are not part of an organised movement) also show elements of insanity. Other motivations may be money (as in the case of a contract killing), revenge, or as a military operation.
The euphemism targeted killing (also called extrajudicial execution) is also sometimes used for sanctioned assassinations of opponents, especially where undertaken by governments. 'Assassination' itself, along with terms such as 'terrorist' and 'freedom fighter', may in this context be considered a loaded term, as it implies a despicable act - whereas the proponents of such killings may consider them justified or even necessary.