lazzi is the plural of the italian word lazzo that currently means "verbal joke". The word is falling out of use, its original meaning is "bitter, astringent"; one famous use is in the Divina Commedia:
ti si farà, per tuo ben far, nimico;
ed è ragion, ché tra li lazzi sorbi
si disconvien fruttare al dolce fico.
, V 64), meaning, "because of your good deeds, they will become your enemies/which is reasonable, since among the bitter rowans/the sweet fig should not bear fruit
". Here Brunetto Latini
is foretelling Dante
's future; the Florentine
s will become his enemies (and exhile him) because of his integrity
In Italian, lazzi is often used in the idiom frizzi e lazzi, which means "jokes of all types". I do not know in what a "frizzo" would be different from a "lazzo"; it could be just an alliteration, like "cazzi e mazzi" or "flotsam and jetsam".