The word "弑君" is a verb-object compound formed by combining the character "弑", which specifically means to kill a superior such as a ruler or parent, with "君", meaning monarch or ruler. The character "弑" itself is composed of the radical "杀" denoting killing and the phonetic component "式" indicating pronunciation, but in this word, it functions as the action directed at the object "君", resulting in a direct meaning of assassinating a ruler, i.e., regicide.