Agassi is almost unique, Agassini is equally rare, Agasso, extremely rare, it would seem Piedmontese, should be dialectal deformations of surnames such as Agazzi and derivatives, Agazzi is typically Lombard, Agazzini, Agazzone and Agazzoni in particular, very rare, they seem to be from the area between upper Lombardy and Piedmont, Agazzino is almost unique, they should derive from the late Latin cognomen Agathius, of which here we have an example in this ancient Latin tombstone: "... [Aia] ci L (uci) l (iberti) Agato / portitor (is) soc (ii) s (ervus) /  columnasque mag (nas) fi (ctiles) / [3 de s] u Menervai d (onum) d (at) / l (ibens) m ( erito) ... ": we remember Sant'Agatio, a centurion of Cappadocia martyred in Constantinople in 306:" ... Constantinople sancti Agathii Centurionis, here, in persecution Diocletidni et Maximiani, in Firmo Tribuno delatus quod Christianus esset ... " . Traces of the Agazzi in the Bergamo area are to be found as early as the 1400s, while the Agazzini in 1400 are mentioned among the notables of Cassano Magnago (VA). additions provided by Giovanni Vezzelli According to Francipane 260, Agazzi comes from the personal Agàzio, from the Greek-Latin agasia = illustrious; for D. Olivieri 234 from a mess (from lat. acus = needle) or from the Friulian agàzz = gouache, or from the Venetian agazzo = downpour.
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