Wikipedia
The word Trinacria means triangle and refers to the shape of the island of Sicily (“Sicilia” in Italian), the largest island in the Mediterranean. Sicily was known by the Romans as Trinacrium, meaning “star with three points”. The Trinacria symbol is the head of Medusa (a gorgon with a head of snakes), surrounded by three bent running legs, and three stalks of wheat. Due to the island's distinct triangular shape, the symbol has also been adopted by the Sicilian government and is located on the center of Sicily's flag. The Trinacria's shape is often referred to as a triskelion; this shape can be found in many places among the general Mediterranean Basin region and in many European countries like France, Sicily, Crete, Greece, the North African coast, and the Isle of Man. The triskelions found in these locations have all dated back to after the eighth century BC.
Trinacria is an extinct genus of diatom present during the early Eocene.