Silvio Frondizi (January 19, 1907 — September 27, 1974) was an Argentine intellectual and lawyer, brother of President Arturo Frondizi and of the philosopher Risieri Frondizi.
He became active in leftist groups, and was assassinated in 1974 by the Triple A right-wing death squad that operated under the Peron government between 1973 and 1976.
This was before the military juntas and their Dirty War.