What is the Latin word for tyrannicide?

The usual Latin words for “tyrannicide” are tyrannicīdium, tyrannicīda. The right choice depends on the sense; see the distinctions below.

English → Latin

“tyrannicide” in Latin

tyrannicīdiumtyrannicide tyrannicīdaone who kills a tyrant, an assassin

The English word tyrannicide itself goes back to Latin tyrannus, through tyrannicīda.

Riddle & Arnold A Copious and Critical English–Latin Lexicon, 1864

tyrannicide

tyrannicidium (the killing of a tyrant, Sen., Plin., Quint.); tyranni interfector (Liv.); tyrannicida (Plin.); tyrannoctonus (Cic.; one who has killed a tyrant).

Quick answer

What is the Latin word for tyrannicide?: The usual Latin words for “tyrannicide” are tyrannicīdium, tyrannicīda. The right choice depends on the sense; see the distinctions below.

Entry from J. E. Riddle & T. K. Arnold, A Copious and Critical English–Latin Lexicon (rev. C. Anthon, New York: Harper, 1864), digitised by Fergus J. P. Walsh, CC BY-SA 4.0; Latin markup adapted by latindictionary.co.