overt act /ō-'vərt-, 'ō-ˌvərt-/ n
1: an act directed toward another person that indicates an intent to kill or harm and that justifies self-defense
2: an outward act that is done in furtherance of a conspiracy, of treason, or of the crime of attempt and that is usu. a required element of such crimes for conviction even if it is legal in itself
Merriam-Webster’s Dictionary of Law. Merriam-Webster. 1996.