Iacona is Sicilian, Iaconelli seems to be typical of the southern area of the province of Frosinone, Iaconi has a stock in the Reggio area and one in the area of Teramo, Iaconis is typical of Calabria, especially of Acquaro (VV), San Giovanni in Fiore (CS), Laureana di Borrello and Giffone (RC), Iacono has two important stocks, one in the Neapolitan and one in southern Sicily, Jacono seems to have been born in the Milanese, perhaps from different transcriptions of the previous surname, the derivation of all these surnames should be from nicknames indicating the position of Deacon occupied by the progenitors, although it cannot be excluded that in some cases they may be contracted forms of the augmentative of the name Isaac. Traces of these surnames can be found, for example, in Acquaro (VV) since the 1700s with the Prosindico Francesco Iaconis and in Mileto (VV) with the archpriest Pasquale Iaconis.
Definitely of Sicilian origins, all but Loiacono which would seem to have two stocks, one Calabrian and one in Bari. All these surnames derive from nicknames indicating the characteristic function of Deacon.
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