Dirty bomb

A dirty bomb is a conventional bomb used to distribute radioactive materials. That is to say, it is not a nuclear weapon and no chain reaction takes place, but the bomb site becomes contaminated and the general fear of radioactivity will cause most of the harm.

The term was put in focus on June 10, 2002, when U.S. officials announced they had captured an al Qaeda terrorist in Chicago a month earlier, who was allegedly planning for such a dirty bomb.