Regicide

1. (n.) The killing or the murder of a king.

2. (n.) One who kills or who murders a king; specifically (Eng. Hist.), one of the judges who condemned Charles I. to death.

Thesaurus Entries

aborticide, fratricide, fungicide, genocide, germicide, herbicide, homicide, infanticide, insecticide, matricide, microbicide, parricide, patricide, pesticide, rodenticide, sororicide, suicide, uxoricide, vermicide