Cosmo m
Italian, English, and German: Italian form (also found as Cosimo) of the Greek name Kosmas (a short form of various names containing the element kosmos order, beauty). This was borne by a Christian saint martyred, together with his brother Damian, at Aegea in Cilicia in the early 4th century. It was first brought to Britain in the 18th century by the Scottish dukes of Gordon, who had connections with the ducal house of Tuscany. The name was traditional in that family, having been borne most famously by Cosimo de' Medici (1389–1464), its founder and one of the chief patrons of the Italian Renaissance.
First names dictionary. 2012.