You searched for: “regicide
regicide (s) (noun), regicides (pl)
1. The killing of a king, especially someone who kills his/her own king: Charles I was a terrible king, and after a trial, was committed to death, and this regicide was the first of its kind.
2. Someone who commits the crime of murdering a king: John Jones, Adrian Scrope, and Gregory Clement are just three regicides who were arrested, found guilty, and were either hanged or drawn and quartered.
This entry is located in the following units: -cide, -cides, -cidal (page 10) regi-, reg-, rec-, rex- (page 8)