Surnames Giachino, Giaccone, Giacconi, Giacheri and more

Giacalone, Giacardi, Giacaz, Giaccagli, Giaccaglia, Giaccaglini, Giaccardi, Giaccari, Giaccheri, Giaccherio, Giacchétti, Giacchi, Giacchin, Giacchini, Giacco, Giaccone, Giacconi, Giacheri, Giachero, Giachetti, Giachi, Giachin, Giachini, Giachino
they are derived from the given name Giacomo.
In some regions of Italy, the contraction (ie the loss of a syllable) gave rise to Giaco and from there numerous suffixed variants arose. The Italian practice of shortening names by dropping off syllables, was also typical during the medieval ages.