Tomarchi is almost unique, Tomarchio is specific to the Catanese, should derive from the Byzantine term Turmarco, charged in use by the Army of the Eastern Roman Empire that identified those who were in command of a Torma or group of thirty Knights (Turma Arche = a Head of a men's tower). Integrations provided by Giovanni Vezzelli Tomarchio is a surname of eastern Sicily and is a variant of the surname Trimarchi which derives from the Byzantine Greek tumàrchis = Governor of a district. Rohlfs, 188.
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