From the word for a measure of weight, from southern dialects, derived from Greek via Arabic.

A Sicilian surname of dialect origin. It comes from the word ròtulu, with the meaning of "an ancient Sicilian unit of weight." The rótulo was equivalent to 0.793 kg (30 Sicilian ounces) and comes from the Arabic raṭl, adopted in turn from the Byzantine Greek lítra. It was the main unit of weight of Sicily from its introduction during the Islamic domination (9th century) until the Italian unification of 1860: almost a thousand years of continuous use across all the subsequent dominations. Its wholesale multiple, the cantar, was equivalent to a hundred rótuli (79.3 kg) and was used in port trade. As a surname it may have originated in the office of the public weigher, a municipal official whose seal of authority determined the weight in commercial disputes.